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THE PROBLEM DESCRIPTIONWhen the computer is booted, everything looks fine initially with all the Desktop icons and the Task bar. The programs appear to be running fine. But all the icons and task bar disappears suddenly. Then it all reappears and this process continues without letting the user to perform any tasks.
This problem recurs always when the computer is booted.
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THE PROBLEM IDENTIFICATIONThe above described problem appears due to corrupt EXPLORER.EXE file. This may have happened due to some trojan attack through internet file downloading. The solution in this article deals with solving this problem. However, it is recommended to reinstall Windows XP some time soon.

3. ACCESSING C:\WINDOWS FOLDERIf the task bar is not visible at all, you will need to press Ctrl Alt Del key to bring up the taskbar. Go to 'New Task' from the menu bar and enter 'explorer.exe'. You will need to do this several times if your task bar disappears again.
Go to 'C:\WINDOWS' folder through 'My Computer'. If accessing the My Computer folder is not possible then you can go to Command prompt by typing 'cmd' in the 'Run' command line and accessing the 'WINDOWS' folder from here.
4.

COPYING AND RENAMING EXPLORER.EXE FileCopy the EXPLORER.EXE (Computer icon) file and paste it in the same folder. A file 'Copy of EXPLORER.EXE' will be created in the folder. Now change the file name to your name.exe. For example, I renamed mine to 'deshmukh.exe'
5.

CHANGE REGISTRY - REGEDITNow go to Start >> Run and type 'regedit' and press enter key. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\Current Version\Winlogon. In this folder, you will find a sub named 'shell'. Double click it and rename the 'explorer.exe' to 'deshmukh.exe'
6. RESTARTRestart your computer after making this change. Everything will be back to normal without any problems!