Boot into Safe Mode.. At the login page, choose the "administrator" login (or type "administrator"), then leave the password blank and press the "Enter" key.. If you've never created a password for the hidden "administrator" login, then the computer should start.. From there, you should be able to give your original username a new password.. Unfortunately, it's entirely possible that your original user account is corrupted because it shut down incorrectly.. If that's the case and you can login from the administrator account in Safe Mode, then simply create a NEW account, with a new user name, give it admin rights, and login normally using the new account.. Once there, you can copy the files from your old account, into the new account.
Hope this helps.
Grif
I have a netbook and when using it one day, not plugged in, it went on standby due to a low battery. I had noticed the battery was low but there was some work I was wanting to finish off. I have had this happen before and it doesn't shut of completely normally just goes to sleep and if you press power again it will come back on briefly normally giving you enough time to power off correctly. I therefore turned it on, saved some work I was doing and then it went on standby again so I switched it back on quickly then shut it down properly. However, the next time I went to use it I forgot it had been low on battery so I switched it on an it powered off without even starting fully so I found the adapter and plugged it in and from here I have not been able to use it outwith safe mode as no username appears and nowhere for me to enter my password. from online help I have tried:
Pressing CTRL+ALT+DEL (x2) to bring up some background logon screen. I've been advised that the username should be admin, administrator, username, the username I have previously and the password should be admin, password or the password I would normally use. I have tried numerous combinations of these with no success.
Having failed with this the next thing I tried was to enter the comp in safe mode and from there set up a new username via control panel. I was unable to do this as from control panel it would not allow me into the user accounts screen. A pop up appears restricting me from it and on clicking OK a blank section appears in the window.
Next thing I tried was sorting the issue with registry editor. From the user list folder I set up a new DWORD value, named it Haggis which was my username and set the value to 1. I then restarted the computer and still I arrive at the logon screen and the only option I have at this point is to basically switch it off again.
I have also tried a system restore to no avail.
Can someone please help as I have things on it I do not seem to be able to find and locate from safe mode. I was going to transfer them onto an external hard drive so at least I had those files but nothing could be located! I assume it was linked to the low battery on off issue hence why I included that at the start to better diagnose the issue.
Your help would be greatly appreciated.
Brian

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic