XP Pro won't switch users

I have recently installed XP Pro on my home computer. Everything seems to work fine until I try to switch users. When I try to switch users, it keeps looping back to the Welcome/Login/Choose User screen.
I'll click on a name, it will look like it's trying to load that profile, and then it will go back to the screen with the choice of profile names. The only way I have found to change from one user to another is to reboot.

I apologise if this has been addressed elsewhere, but I did not see it.
Thanks.

 

is this a clean install? updates applied?

do u have anything in startup that shouldn't be there or have u installed any of the powertoys for xp?

is this a domain logon or standard local logon?

can u create a new user and see if the problem persists when switching?

 

This was a clean install, complete with hard drive formatting. I really haven't installed much of anything save the Norton Anti-Virus, which seems to be running well.
As for domain vs. local logon, this is a standard, local logon. I've tried to go to the microsoft update site and get all the necessary updates as well. When I get home this evening, I will try to create a new user ID and see what happens.

Thanks for the suggestion.

 

It still does the same thing. There seems to be a loop back to the "choose user" screen. Even the new profile won't load unless I reboot

 

This is by now an old thread, but the problem has happened to me as well.
I wonder if Macey tried pressing the Windows log +L which "unlocks" Windows.
My problem co-incided with many windows settings being disabled ,(see Control Panel, Admin Tools,Computer Management, Services) - no trojans found but all is not yet well with switching user option.