What you don't want to read, but I must write is that you may have to power off the machine or press that reset button.
If you can log back in, then head to the display properties and hopefully you haven't been infected with a recent worm/virus/pest/malware that changed the password.
If there was a "backdoor", this would be fixed immediately since such a feature would be a security risk.
Best of luck,
On another computer I have a password on my screensaver and a password on my computer for when it restarts. I have windows 2000. Today my screensaver came on and when I went back on the computer and typed in my password it said that I didn't type in the right password. So I did it a few more times and it still didn't work. I've been trying ever since. I checked to make sure that I don't have on caps lock and I don't. I was wondering if there's something that maybe I can type in just so I can get in to change the password or something.
Any help is welcomed