When I installed XP it never gave me the opportunity to set the
password for the default Administrator account ... I gave my own
account administrator rights. Later on I found out that my default
Administrator didn't have a password assigned to it, so I had to
assign one.
The point I'm trying to make is that w/o a password for an
Administrator account you can't even boot into Safe mode...but there's
a trick around that only I'm not sure exactly what it is ... possibly
when you get to the part where the system is asking for the Admin
password you might just be able to hit Enter and that may allow you to
enter Safe mode ( tap F8 while booting ). It's that or hit
Ctrl-->Alt-->Del either once or twice and that may let you in. Try
all three to see what happens.
If you can get in this way, select "Safe mode"; Go to
Start-->Programs-->Accessories-->Command Prompt.
At the command prompt type in "net localgroup administrators" minus
the quotes ... this will bring up a list of users with Administrator
rights. If the default Administrator is listed there (it will just
say Adminstrator) and it doesn't have a password yet, you'll need to
create an account and assign it Administrator rights and then do
Start-->Run and type in "control userpasswords2" minus the quotes and
hi-lite Administrator and choose "make password" or something like
that. That should solve that problem. You should also go back and
remove the user account that you created from the Administrator
group...assign it with "Limited use" authority, and use that account
for day-to-day use. That way if you should pick up a virus or trjan
or whatever, it won't be able to do system-wide damage. Use the
Adminstrator account ONLY to make system changes or to install
programs, etc.
I know this is a bit winded, but the only other thing I know to do is
to re-install the OS