Lost personal settings on boot up XP

[hillneerg]

Strange thing happened today. I switched on the PC and instead of loading up my usual desktop etc, it appeared to be reinitializing the whole thing (like setting up a new user).
When it finished, all my personal stuff (my documents etc) were empty and only a few icons remained. Opening Firefox resulted in a welcome screen (as though I had never used it before). The only time I have seen this happen was after a reimstall of the OS last year.
I tried a rollback to a couple of days ago but it said it was unable to do so BUT my normal desktop etc reappeared and everything was normal again.
I'm an experienced user but this has me baffled. The only thing I have done that was "unusual" was to update my virgin mail the previous night via their website (as requested) due to some changes they had made.
The PC switched off normally last night.
I just switched it on again this morning and this happened. (no, didn't have the setup disc in).
There's no traces of malware etc (fully scanned the PC to be sure with Trend Micro, Spybot and Malwarebytes - all clean).
If someone could possibly offer an explanation into a possible cause, I'd be very grateful.
I just can't figure this at all.
Running XP Home SP3, 1.7 CPU, 1 Gig Ram.
Thanks.

 

[JMMD]

Could be that the user profiles was corrupted and a new user was created. When that happens you can recreate the old user and copy everything over and that should return everything to the way it was before.

 

[hillneerg]

OK, a little update on this.
It booted fine for a couple of days and then, today, I sat by the PC while it booted and it flashed a box saying it was unable to find my user profile and was starting a temporary profile for the session. I must have missed that the first time.
I pulled the plug before it did so and restarted the PC. This time it booted normally.
Any suggestions as to a possible cause would be appreciated.
I do dislike things that happen only occasionally.
Thanks