start up problem

[gtp]

I've been running XP for about 9 months, when I went to turn on my PC today
I get a box that asks me for a password (this box never came on before) then
the PC shuts downs and tries to reboot itself. I tried attempting to start
in Safe Mode but I am unable to get the mouse to work or move the cursor to
make the selection on Safe Mode. Has anyone had a problem like this and is
it possible its the result of a virus. (I was running anti virus software).
Any help would be greatly appreciated.Thanks, Traveler

 

[JAX]

To get to safe mode, you use your up and down arrows to select and then
press enter.

JAX

 

[ThePainter]

If you are the only user account you would not have been
asked for a password before , one of the updates for .NET
environment adds its own account so now there are 2 so it
asks for you to log in if you dont have a password just
leave it blank and log in .then :start>run>CONTROL
USERPASSWORDS2 this will open a box where you can
configure to log straight into your account.