Can't Login from welcome screen! Help!!

[Guest]

I turned my computer off last night and when I turned it back on this morning, everything booted up as normal and this welcome screen is displayed, however, my administrator info. is gone and I cannot login. I am stumped. What do I do? I have Windows XP Professional (cannot find my CD anywhere).

 

[Guest]

i have the same problem.
When i boot up my computer it seems to start up
just fine but, when the login screen comes up there are no login
applets. that is, my administrator login and guest login are not to be
found. i can still move the mouse but thats about it. i have tried
starting in 'safe mode' and 'restarting to the last known good
configuration'. both have proved the same results of just a log in
screen with out the applets to actually login. is there any way around
the login process to windows xp? i figure that this is a result of a
changed login setting or possibly a missing file. i do not know how
this problem came to be because i was not the last one to use the
computer before this started happening. i still have not tried using a
boot disk to start up. any additional ideas and or suggestions would be
greatly appreciated. thank you for your time.