XP keeps looping

Hi folks, I am posting this message for my brother in law (Kev)who lives 120 miles away and has been keeping me awake the last couple of nights with long phone calls about the problem with his PC. Kev returned home after a weeks holiday and went to use his pc Pentium4HP running XP-SP2 and MS IE and did some surfing, collected a few emails which he tells me looked ok. he then logged off ……….. he thinks there may have been some sort of download occuring possibly Win XP updates, but he's not sure……… anyways when he came to use the pc again it refuses to boot up stopping at the "blue screen" and then restarting it self after, have tried to start in safe mode but although the safe mode blue screen is displayed the pc will just go into another restart cycle. Have managed to load and run the recovery console but we dont really know what to look for, also Kev used his original XP cd to "clean up XP" this took about 35 minutes to complete and the only difference is that the pc hangs on the "blue screen" for about 30 seconds now instead of going into an immediate restart loop. Any ideas, suggestions for using recovery console or is it a case of reinstalling XP from scratch and losing application files, phots etc? Also does th XP "clean up" process mean that XP is now back to SP1 or what? I will look for a rely later, ta.

Hi there cboy, Thanks for the ref. to those two sites - the repairXP site turned up trumps with a fairly straight forward routine to follow to repair boot sector which appears to have done the trick. yes you were correct about the black screen for entering safe mode, I should have said that once you selected safe mode the pc proceeded to look as if it was starting in safe mode ie a blue screen with safe mode in four corners appeared but then it just restarted. Once again many thanks for the info