I have W2k server spk4, HP ML350g4, 1mb ram, P 1.4gig. I can boot system to desktop after screen saver pops in and I try to log on (Ctrl+Alt+Del) put in password I get the following display: "The system can not log you on due to the following error: The network request is not supported. Please try again or consult your system Administrator" If i reboot system I am able to log in, but the problem comes back. Thanks for any help.

Do you use a domainserver? Then pay attention when you try to log in again: Maybe it's on the local domain (the pc) and not on the network-domain (or vica versa).

this may seem wired but what about changing your password mite be the computer just dose not like it?

Check you keyboard settings of your default profile.

When you are not logged on yet, windows uses the keyboard setting of the default user profile.
Once logged-on you get your own keyboard settings.
IF there are differeces between those this can be the case.

To do a test , type the pasword for the log-in in the usernamefield and see how it looks like.
Do the same after the PC has been locked , then also type the paswoord in the username field so you can see if there are differences between those.:o