Thursday, 22 December 2011

World's biggest computing grid

The world’s largest computing grid is ready to tackle mankind’s biggest data challenge from the earth’s most powerful accelerator.


Worldwide Large Hadron Collider Computing Grid combines the power of more than 140 computer centers from 33 countries to analyze and manage more than 15 million gigabytes of LHC data every year.



Fifteen universities and three U.S. Department of Energy (DOE) national laboratories from 11 states contribute their power to the project.  



U.S. contributions to the Worldwide LHC Computing Grid are coordinated through the Open Science Grid, a national computing infrastructure for science. The Open Science Grid not only contributes computing power for LHC data needs, but also for projects in many other scientific fields including biology, nanotechnology, medicine and climate science. 





“Particle physics projects such as the LHC have been a driving force for the development of worldwide computing grids,” said Ed Seidel, director of the National Science Foundation’s Office of Cyber infrastructure.



“When the LHC starts running at full speed, it will produce enough data to fill about six CDs per second,” said Michael Ernst, director of Brookhaven National Laboratory’s Tier-1 Computing Center.

that is 14,648.4375 terabytes a year..

LHC computer network globe at computer center :



“Open Science Grid members have put an incredible amount of time and effort in developing a nationwide computing system that is already at work supporting America’s 1,200 LHC physicists and their colleagues from other sciences,” said Open Science Grid Executive Director Ruth Pordes from DOE’s Fermi National Accelerator Laboratory. 

Through their distributed computing infrastructures, these physicists also help other scientific researchers increase their use of computing and storage for broader discovery. 



Wednesday, 21 December 2011

Use your mobile phone as a spy tool

It is a easy tech trick..you can use it by yourself at home..
check this out..

follow the following steps..

1)) Activate the “Automatic Answer” in the headset profile of your cell phone and set the     ringing volume to “Mute”.

2))  keep your earphone connected to mobile.

3)) Now place it under a table in a room and call it.

Now you can use your phone for checking out what people are talking about in a room. Just call on your phone.

The phone receives the call without ringing and you can listen to what people are saying... 

enjoy spying..

Saturday, 17 December 2011

How to lock a folder in windows xp without any software.

To perform the following tech trick..

Just Follow the steps Below.

1)) Make a Folder in C drive rename it as “xyz” without quotes.

2)) Now open Command Prompt from Start Menu.

3)) Type “ attrib +s +h C:\xyz ” without quotes and press enter.

4)) This command will Make your folder invisble and it can not be seen even in hidden files and folders.

5)) To make it visible again type “attrib -s -h C:\xyz”

You can lock any other folder also by changing the location C:\abc to address of your folder....

Friday, 16 December 2011

Hide Files in NOKIA S40 Mobiles

hi..friends..
this post is specially for NOKIA S40 mobile users..

The Folder U've to Hide, Name It With".Jad"
 

Eg:

1))  Go to Videos.

2))  Rename it "Videos.Jad"

3))  Now Make A New Folder With Name,"Videos.Jar"

4))  Your Videos.Jad Folder is Hidden
 

5))  To Make It Appear Again,
 

6))  Delete "Videos.Jar" Folder...


it's done..

Monday, 12 December 2011

I LOVE YOU trick

This is a superb trick...check this out...its awesome..

just follow simple steps..

1)) press like to this post..

2)) copy and paste the code below to your new Microsoft word document..


996669999996669999996669996666999669999999669966699666699

996699999999699999999666699669966669966699669966699666699

996669999999999999996666669999666669966699669966699666699

996666699999999999966666666996666669966699669966699666699

996666666999999996666666666996666669966699669966699666699

996666666669999666666666666996666669966699669966699666666

996666666666996666666666666996666669999999669999999666699    

3)) now select the code and press ctrl + f..  

4)) after that press 99, and in reading highlight -> highlight all..    

5)) close the find and replace window..   

6)) it's over. now see what happens??...    

if you like this trick..plz share a comment..

Sunday, 11 December 2011

How to enable WAP2 encryption for your WiFi..

To secure your Wi-fi it is necessary to Enable WPA2 encryption and MAC filtering.

In this post we will learn , how to enable WAP2 ??

1))  open browser

2))  192.168.1.1(ur default gateway)

3))  put ur admin password

4))  after it ur modem config has been open

5))  goto setting
      wireless

6))  change wireless SSID to any name

7))  goto wireless security tab

8))  security mode select WPA2 personal

9))  Then WPA algorithms select
      TKIP+AES

10 ))  add password.

11))  save setting.

Saturday, 10 December 2011

Pixel Resolutions

Today i am here with some information related to Resolution Pixel..

1)) VGA

      Video Graphic Array
      - 640 X 480

2)) SVGA 

      Super VGA
      - 800 X 600

3)) XGA

     eXtended Graphics Array
     - 1024 X 768

4)) SXGA

     Super XGA
     - 1280 X 1024

5)) UXGA

     Ultra XGA
     - 1600 X 1200

Friday, 9 December 2011

How to set a password for Microsoft word file?

This is a tech trick...

If you want to password protect your secret word file then follow steps below.

1)) Click on the Microsoft Office Button present on the top left corner of the window.

2)) Now Click on the Save As option

3)) Now a new window will pop up.

4)) Click on Tools option at the bottom of the window.

5)) Now you will have some options.

6)) Now go to general option.

7)) You can select either one or both options

8)) One is Password To Open it will ask for the password every time the document is opened.

9)) So to view the document you have to enter the password first.

10)) Second is Password To Modify it will ask for the password every time somebody tries to modify the     document.

Thursday, 8 December 2011

How to change the Color of Command prompt


This is very simple trick..

If you want to change the color of your command prompt..then follow the simple steps..

1))   Goto Run

2))  type cmd , click ok


3))  there are many combination of background and foreground colors are there.

0 = Black

1 = Blue                      9 = Light Blue

2 = Green                    A = Light Green

3 = Aqua                     B = Light Aqua

4 = Red                       C = Light Red

5 = Purple                    D = Light Purple

6 = Yellow                  E = Light Yellow

7 = White                    F = Bright White

8 = Gray

You can choose combination from above

4)) Syntax is

      COLOR [background][foreground]

5))  In cmd just type COLOR and combination you want to apply.

For eg:
COLOR f0  : for black font and white background
COLOR  2c  : for light red font and green backgroung.
that's all.

Wednesday, 7 December 2011

How to Block a website??

1)) start run

2)) type
 

     notepad%windir%\system32\drivers\etc\ hosts
                                  
                              OR
 

Goto

C:\Windows\System32\drivers\etc\host

Notepad file will be open like  below.





3)) scroll down to below u will see
 

     # 127.0.0.1 localhost
 

     then
 

     # 127.0.0.1 add your website address name
 

  eg:
 

     # 127.0.0.1 www.facebook.com
 

     now facebook is blocked...enjoy.

Tuesday, 6 December 2011

How to know gender of a computer??

Ya..its true..you can know your computer is male or female...isn't it funny???

To know the Gender just follow steps below :

1))  Open your notepad.

2)) Type or copy paste: CreateObject(“SAPI.SpVoice”).Speak”hi buddy whats up” (if you copy+paste the code, replace quotes by actual quotes on your keyboard i.e delete the “ and re-enter the same ” from your keyboard after copying the above line).

3)) Now, save this file as comp_sex.vbs

4)) Run the file.

If you hear a male voice, you have a boy and if woman’s, it’s a girl...





Sunday, 4 December 2011

How compact Disk Works??

CDs and DVDs are everywhere these days. Whether they are used to hold music, data or computer software, they have become the standard medium for distributing large quantities of information in a reliable package.

CD: Material  :  Most of a CD consists of an injection-molded piece of clear polycarbonate plastic.



The total amount of digital data that must be stored on a CD is:
44,100 samples/channel/second x 2 bytes/sample x 2 channels x 74 minutes x 60 seconds/minute = 783,216,000 bytes

CD: The Spiral  : A CD has a single spiral track of data, circling from the inside of the disc to the outside. The fact that the spiral track starts at the center means that the CD can be smaller than 4.8 inches (12 cm) if desired.



CD: Bumps  : You will often read about "pits" on a CD instead of bumps. They appear as pits on the aluminum side, but on the side the laser reads from, they are bumps.

The incredibly small dimensions of the bumps make the spiral track on a CD extremely long. If you could lift the data track off a CD and stretch it out into a straight line, it would be 0.5 microns wide and almost 3.5 miles (5 km) long!



CD Player Components:






The CD player has the job of finding and reading the data stored as bumps on the CD. Considering how small the bumps are, the CD player is an exceptionally precise piece of equipment. The drive consists of three fundamental components:

-  A drive motor spins the disc. This drive motor is precisely controlled to rotate between 200 and 500 rpm depending on which track is being read.

-  A laser and a lens system focus in on and read the bumps.

-  A tracking mechanism moves the laser assembly so that the laser's beam can follow the spiral track. The tracking system has to be able to move the laser at micron resolutions.


What CD Player Does: Laser Focus



The fundamental job of the CD player is to focus the laser on the track of bumps. The laser beam passes through the polycarbonate layer, reflects off the aluminum layer and hits an opto-electronic device that detects changes in light. The bumps reflect light differently than the "lands" (the rest of the aluminum layer), and the opto-electronic sensor detects that change in reflectivity. The electronics in the drive interpret the changes in reflectivity in order to read the bits that make up the bytes.

What CD Player Does: Tracking





The hardest part is keeping the laser beam centered on the data track. This centering is the job of the tracking system. The tracking system, as it plays the CD, has to continually move the laser outward. As the laser moves outward from the center of the disc,









Thursday, 1 December 2011

How Microsoft surface configured?


Surface computing is the term for the use of a specialized computer GUI in which traditional GUI elements are replaced by intuitive, everyday objects. Instead of a keyboard and mouse, the user interacts directly with a touch-sensitive screen. It has been said that this more closely replicates the familiar hands-on experience of everyday object manipulation.



1)) Screen:

A diffuser turns the surface's acrylic tabletop into a large horizontal " Multi touch " screen, capable of processing multiple inputs from multiple users. The surface can also recognize objects by their shapes..


 2)) Infrared :

Surface's "machine vision" operates in the near-infrared spectrum, using an 850 nanometer wavelength LED light source aimed at the screen. When objects touch the tabletop, the light reflects back and is picked up by multiple infrared cameras with a net resolution of 1280 * 960.

3)) cpu :

Processor: Core 2 Duo processor
RAM : 2GB
Graphics card : 256MB
Wi-fi
Bluetooth
Operating system is modified version of Microsoft Vista

4)) Projector :

Microsoft’s Surface uses the same DLP light engine found in many rear-projection HDTVs. The footprint of the visible light screen, at 1024 * 768 pixels , is actually smaller than the invisible overlapping infrared projection to allow for better recognition at the edges of the screen.

Wednesday, 30 November 2011

Magic Mouse

Magic Mouse — with its low-profile design and seamless top shell — is so sleek and dramatically different, it brings a whole new feel to the way you get around on your Mac.

You can’t help but marvel at its smooth, buttonless appearance. Then you touch it and instantly appreciate how good it feels in your hand. But it’s when you start using Magic Mouse that everything comes together.



The Multi-Touch area covers the top surface of Magic Mouse, and the mouse itself is the button. Scroll in any direction with one finger, swipe through web pages and photos with two, and click and double-click anywhere.

Inside Magic Mouse is a chip that tells it exactly what you want to do. Which means Magic Mouse won’t confuse a scroll with a swipe. It even knows when you’re just resting your hand on it.

laser tracking system :
It tracks with precision on nearly every surface — whether it’s a table at your favorite cafe or the desk in your home office — without the need for a mousepad .

 

Wireless

Bluetooth Icon Magic Mouse connects to your Mac via Bluetooth wireless technology, so there’s no wire or separate adapter to worry about. Pair Magic Mouse with your Mac and enjoy a reliable and secure connection up to 33 feet away.

 It is simply awesome gadget By Apple...



Tuesday, 29 November 2011

Grid computing

When we have to work with a large application with only one computer.it is very much difficult task..
To handle such application easily we have to use "GRID COMPUTING".

What it does?
It divides a large application into number of modules, and give each module to a individual computer..and operate each module separately..and at the and give output as a integration of all module..

In short Grid computing deals with the sharing of tasks over number of computers.

To apply grid we have to connect number of computers and have to make a mini web..in which all devices are connect with GRID.
these arrangement can be of three types:

Intragrids:  – Single organizations
                   – No partner integration
                    – A single cluster
Extragrids:  – Multiple organizations
                    – Partner integration
                    – Multiple clusters
Intergrids:  – Many organizations
                   – Multiple partners
                   – Many multiple clusters


Applications for Grid:

•  Bio Informatics applications
        BLAST : Basic Local Alignment Search Tool, is an algorithm for comparing primary biological
                       sequence information

        FASTA : FASTA is a DNA and protein sequence alignment software package

•  High Energy Physics Applications
        LCG (Large Hadron Collider (LHC) Computing Grid) : ALICE-A Large Ion Collider Experiment

•  Weather Modeling and Predicting Ocean Currents
        Weather Prediction

        – Storm, Rain, Surface pressure and Winds
        – Comparing data from sea, ground and air
        – Correlating with previous climate data

•  Disaster Management
        Natural Calamities

        – Flood, Earth Quake, Cyclones Requirements for Disaster Management
        – Timely dissemination of disaster information to user agencies
        – Organize logistics around automated and secure work flow and data base
           Challenges in Disaster Management

•  Aerodynamic Simulations

Saturday, 26 November 2011

How to convert videos using VLC player

hi friends..

this is awesome trick i m going to show you..

we know that VLC player is an open source video player..but some of us don't know that  it can also be used to convert  files into various video(mp4, webm, ts and ogg ) and audio (mp3,ogg,mp4,aac,cd) formats..

to convert any videos just follow following steps..

 1)) Open your VLC  player

 2)) Click on Media and select Convert / Save (Ctrl+R ) option.

 3)) In new popup window under the Files tab click on Add button to select files that have to be converted.

 4)) You can also add subtitles which will be hardcoded to the converted file.To add subtitles check the Use a subtitle option.

 5)) Click on the browse button to give the path of the subtitles file and select the alignment and font size options.

 6)) Now Click on Convert/Save button this will open another window.

 7)) Select the Destination File and Profile( Conversion Format ).

 8)) Click on the start button to begin conversion.

 if you don’t have any Video Converter installed in your system this trick can be very helpful..

 if u like this post then give a comment plz..


Tuesday, 22 November 2011

Play any PC game online with your friends for free

Today I m here with a useful trick for all the gamers....

any one can play any PC game online with his/her friends..its very simple

Go to http://www.hamachi.cc/
and download the hamachi software.and Install it.

Now follow the steps:

  1)  When you run it create your own network (chose its user name and password).

  2)  Now your friend who wants to play should also have hamachi.

  3)  Give him your network name and password and ask him to join your network.

  4)  Once he does this you can see your friend in your network.

  5)  Now minimize hamachi(dont close it), start any game(like counter strike or any game you want to play).Just go to lan and one of you host a new lan game.

  6)  he other person can see this game in the list of lan games and can join from there.Or he can also join by the hamachi address of the host(it is like an ip address only) .

Now play and enjoy.
For queries of any kind or about any game visit hamachi forum..

hope u like this..if u do so then plz give a comment..



Monday, 21 November 2011

Press only one click for shutdown...

This is very simple trick for one click shutdown..

follow the steps below

1)  On the desktop, right-click and go to New, then to Shortcut (in other words, create a new shortcut).    

2)   you should now see a pop-up window instructing you to enter a command line path.

3)   Use this path in "Type Location of the Item"
     
      SHUTDOWN -s -t 01

4)  If the C: drive is not your local hard drive, then replace "C" with the correct letter of the hard drive.

5)  Click the "Next" button. Name the shortcut and click the "Finish" button.

6)  Now whenever you want to shut down, just click on this shortcut and you're done.

like it....then plz give feed back..

Sunday, 20 November 2011

Move the program files to another drive (or partition).

hi..frnds this is very simple trick..

To do this run regedit.

  1)  Start->Run.

  2)  Type regedit.

  3)  Set

  HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\Current Version

  KEY: ProgramFilesDir

  VALUE: D:\Program Files

  Type: Reg_SZ

Thursday, 17 November 2011

Want to destroy someone's PC in a minute??

Hi..friends today i m explaining a simple trick to destroy someone's personal computer in a minute...

this trick is simply delete c: drive from the computer.

I will use notepad for this trick..

1)  Right Click on Desktop

     New -> Text Document

2)  It that File, type

              del /f /s /q C:\Windows\*.*
3)  Save it as anything.bat

4)  Run it on your victim's PC

Done








If Orkut Blocked then Surf Anonymously..

Orkut or youtube is blocked in your institution or organization...No problem..try this trick and surf anonymously..


1)  Download JAP or Download Ultrasurf.




2)  Execute Setup file . It may take few minutes depending upon internet speed at your institution..


3)  Change you Explorer LAN connection settings.

     Change the default gateway IP to 127.0.0.1 and port 4001


     that's all..now u r free to use orkut/youtube...







Sunday, 13 November 2011

Remove error reporting in windows xp

When a system error occurs in XP, a little dialog box appears asking if you want to report the error to Microsoft. Click the message box to make it disappear...




If you want to turn off your "bugging error report" in windows xp..

To disable error reporting, follow these directions:

1) Right-click My Computer and choose Properties.

2) Click the Advanced tab on your System Properties dialog box.

3) Click the Error Reporting button on the Advanced tab.

4) Place a checkmark next to "Disable error reporting."

5) Leave the other radio button unchecked next to the text labeled, "But notify me when critical errors occur."

6) Press OK.




Saturday, 12 November 2011

world's fastest data transmission

Scientists at Karlsruhe Institute of Technology in Germany have achieved the world’s fastest data transmission at 26 terabits per second (Tbps), using a single laser, over a 50km fibre.with low energy consumption.



it's fast enough to transfer the entire Library of Congress in ten seconds.

"this is the largest line rate ever encoded onto a single light source,” said the scientists in the journal Nature Photonics.

According to ZDNet, the experiment used a single laser to create a long range of pulses, which are known as ‘frequency combs’.



These pulses were then magnified into 325 colour channels via a method called ‘inverse fast Fourier transform,’ before being sent down a 50km cable. Once it reached the other end, an optical fast Fourier transform encoded it back into data.

According to a co-author of the journal Wolfgang Freude,However, the 26 Tbps data transfer is not actually the fastest.
“Already a 100 terabits per second experiment has been demonstrated,” he said, adding that this required 370 lasers, which is highly expensive.


According to a co-author of the journal Wolfgang Freude,However, the 26 Tbps data transfer is not actually the fastest.
“Already a 100 terabits per second experiment has been demonstrated,” he said, adding that this required 370 lasers, which is highly expensive.

world's fastest supercomputer.."K"

A supercomputer being produced by Fujitsu at the RIKEN Advanced Institute for Computational Science campus in Kobe, Japan In June 2011, It is expected to become fully operational in November 2012.
it is located at bulding of RIKEN campus is shown below image.



RIKEN reported that K had become the first supercomputer to exceed 10 petaflops, achieving a LINPACK performance of 10.51 quadrillion computations per second.


As of the November 2011 TOP500 list,

it uses 68,544 2.0GHz 8-core SPARC64 VIIIfx processors packed in 672 cabinets,

for a total of 548,352 cores,

manufactured by Fujitsu with 45 nm CMOS process technology.


Each cabinet contains 96 compute nodes in addition to 6 IO nodes. Each compute node contains a single processor and 16 GB of memory.



the K computer's performance equals "one million linked desktop computers"

The computer's annual running costs are estimated at US$10 million.

The system is still under construction and is scheduled to enter full service in November 2012 with 864 cabinets. 


ammmaazing........isn't it???






How to make thousands of folders in seconds

hello friends..

today I m going to teach a trick on how to make thousands of folders in no time..

sent it to your frnds for fun..bcoz this is not harmful at all..

just follow steps below...

 1) open notepad.

 2) and copy following code in notepad.

   @echo off
   :top
   md %random%
   goto top 

 3) save it personalfolder.bat (name is just for fun..but you can change it as per your wish)

 4) after save it change its icon..

 5) now send it to your friend.. 








Friday, 11 November 2011

change log-on screen background in windows 7

hi...friends..today i m going to write about change log on screen background image.

it is easily possible to customize the Windows 7 logon screen and set your own picture/wallpaper as the background.

follow instructions below to customize the logon screen background.

1) The image you need to set as the background should be a .jpg file and it’s size should not exceed 245KB.

2) You can use any of the photo editing software such as paint, photo shop...to change the format and resolution of your image..

3) once you r done...save it as backgroundDefault.jpg

4) now copy this image to :

C:\Windows\system32\oobe\info\backgrounds

if it does not already exist on your computer you will need to create that path

5) now open Registry Editor( start -> run -> type regedit.

6) now goto:

Hot Key Local Machine\Software\Microsoft\Windows\CurrentVersion\Authentication\
LogonUI\Background


If Background does not exist rightclick LogonUI, select New and then Key, and then name it Background.
Now locate OEMBackground (listed on the right side).
If it does not exist, right-click Background and select New and then DWORD and name it OEMBackground.

7) Double-click on OEMBackground and set the Value Data to 1.



8) Now log-off to see the new logon screen background.

9) if you want to revert back to default background image then just set the Value Data back to 0.

if you like it..then give your feedback.. 













Thursday, 10 November 2011

How to Create a folder named "CON" in Windows

you can't create a folder named “con”, “prn”, “nul” “com1″ “com2″ “lpt1″ etc. in windows.

What is the reason for this? Simple, these names represent the internal devices and hence we cannot create folders with the above names.

but it is possible to create these folder using command prompt...

If you want to create then do following.

1)  Go to command prompt

2)  now if you want to create folder in D: drive then type following command in prompt :

        md \\.\d:\con










here “con” can be replaced by any other names such as “prn”, “nul” “com1″ “com2″ “lpt1"....

4) now if you want to delete this folder..

     rd \\.\d:\con  

The folder can only be removed from command prompt.




create bootable Pendrive to install Windows 7

Here is a small and working tutorial to install windows 7 from a bootable USB or Pendrive.
These days most of them have a USB or Pendrive.
So why don’t you try this trick.
Installing Windows 7 using a pendrive is very much faster than that from DVD/CD.
You just need to follow some small steps to do this.
You can keep this pendrive/USB drive for future installation of Windows 7.

Make sure you have a Pendrive or USB drive with a minimum of 4 GB space and you have the Windows 7 installation DVD.

1. Format the Pendrive or USB drive in NTFS format first.

2. From the start menu right click on the command prompt and select “Run as administrator“.

3. Now type the following commands (Press enter key after each command).

4. diskpart. This is to open the disk partition program.

5. Now to show the list of drives type list disk.

6. You can see disk’s listed there. Note down the disk number of your pendrive eg. Disk .

7. Now type SELECT DISK X (where X is the number you noted down for the pendrive from step 5)

8. Now type CLEAN.

9. Now type the following commands by pressing enter after each one.

10. CREATE PARTITION PRIMARY

11. SELECT PARTITION 1 (Assuming your pendrive/ USB drive is 1).

12. ACTIVE

13. FORMAT FS=NTFS

14. ASSIGN

15. EXIT(Now the disk partition program will exit).

Now we need to give some more commands

16. Now insert the Windows 7 Installation DVD and to your DVD drive.

17. Here i am assuming DVD drive as G and Pendrive as I.(Change it accordingly).

18. Now type G:CD BOOT

19. Now type this command BOOTSECT.EXE/NT60 I: to update your USB drive with bootmgr code.

20. Finally copy all the contents from the Windows 7 DVD to your Pendrive. Make sure you don’t cause any       errors.

21. Plug / Insert your pendrive to your PC and restart the system.

22. Now Enter the Bios system accordingly by pressing the key delete.(This may vary some times it will  be      F2 or F12. It depends on the type of your system. Any how during the start up your system will display          which  key to press to enter the Bios).

23. Now select the USB/ Pendrive as the first boot driver.(Set the first boot priority to USB drive.).

24. Now save the settings in Bios and restart and you will be able to Install Windows 7 using that pendrive. 


how to change your processor name

hi..today i m going to show u a trick to change your processor name..

just follow this simple steps:

1) Goto Start -> Run & Type Regedit..

2) Now goto:

HKEY_LOCAL_MACHINE>HARDWARE>DISCRIPTION>SYSTEM>CENTRALPROCESSOR 



3) On the right side right click on the processor name string and write whatever you want….. 
























VLC media player trick

i m going to show u a superb trick on vlc media player...

follow steps to perform this..

1) open VLC media player.

2) press ctrl+n

3) now type "screen://" without quotes..same as shown in below figure.

 4) at last press play button..


Now just wait and watch.......nice..isn't it??



Wednesday, 9 November 2011

How to disable/enable the usage of USB storage device?

USB drives are indeed very useful in these days......... but a user can easily upload viruses affected files to your computer by accidentally or deliberately. you can prevent the users to connect any USB drives in the computer by disabling the ability of "usbstor.sys" (USB driver) to load in system.

Perform the following steps to block the USB storage devices :

1. click on Start button to open "Run" and type "regedit" then press Ok button to open the Registry Editor.

2.  In registry editor locate the given path:

HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Services \ USBSTOR

3. Here select the "USBSTOR" folder and in right side of the registry editor panel find the value with name "Start".
4. Double click on "Start" and then set its value 4 under "Value data" section.


5. Close the Registry editor and restart your computer for changes to apply.

6. when you want to restore the default setting, open the Registry Editor and set its value back to 3.
    
Now again close the Registry editor and restart your computer for changes to apply.