Hi everyone!

My windows xp logoff immediately after logon. So I have no chance to do anything in windows. This happens in safe mode and for all users too.
The system was working properly before it and it was not connected to network for virus infection. I also checked the problem due to userinit registry key from recovery console and it was correct. Do you have any idea about the problem and solution.

Thanks

Sounds like This covers your issue.
The easy way to fix it is by doing a repair install.
Here's the official Micro$oft way of doing a repair install,
And Here's one with screen shots.

Basically this installs windows over the top of your current setup.
So you don't loose any information you already have.

Thank you curlyben,
But unfortunately a software is installed on this system, which windows repair will lose its registration and this option is completely discarded for this system. Is there any way to solve the problem without win repair.