Sometimes it happens in windows XP that you are not able to open drives on your hard disk. When you double clicking on the drives icons or right click on the drive>>explore in My computer ,the drive does not open

Normally when a virus infects a windows system which causes a drive opening problem, it automatically creates a file named autorun.inf in the root directory of each drive.
This autorun.inf file is a read only ,hidden and a system file and the folder option is also disabled by the virus. This is deliberately done by the virus in order to protect itself. autorun.inf initiates all the activities that the virus performs when you try to open any drive.

You have to just delete this file and restart your system to correct this problem.

Solution 1: (from www.troublefixers.com)

Follow the set of commands below to show and delete the autorun.inf
1. Open Start>>Run and type cmd and press enter. This will open a command prompt window. On this command prompt window type the following steps.
2. type cd
3. type attrib -r -h -s autorun.inf
4. type del autorun.inf
5. now type d: and press enter for d: drive partition. Now repeat steps 3 and 4. Similarly repeat step 5 for all your hard disk partition.

Restart your system and your trouble will be fixed.

Or Solution 2: (from www.techhunt.org)

1) Log in as Administrator or user with admininstrator rights.
2) Turn Off system restore.
Start–>> Right Click My Computer–>> Properties–>> Systen Restore Tab–>>Turn off System Restore on all drives–>> Apply–>> Ok.
1) Launch Task Manager by pressing alt+ctrl+del
2) click on processes tab.
3) Find wscript.exe, If it is running end this process..
4) End EXPLORER.EXE process from Task Manager
5) In task manager, click File–>> New Task (Run..)–>> type cmd –> ok
6) Command prompt will open.Type these commands one by one after Enter key:
del c:autorun.* /f /s /q /a
del d:autorun.* /f /s /q /a
del e:autorun.* /f /s /q /a
c:/ D:/ E:/ are disk drives.
7) Again in Task Manager–>>File –>> New Task (Run…)–>>Type regedit –>> OK.
8. Navigate to the following registry key: HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionWinlogon
9) Find this key: userint.exe
make sure its value is Userinit”=”C:WINDOWSsystem32userinit.exe,
If, It is not, than changed value to this value.
10) Restart system. Done!!!