If your not on a Network and have no use for the Network Logon box do this,
Start>Find>Files, key in *.pwl and press enter. Right click on each and select Rename. Now rename each one you find to .old. For instance, bryan.pwl would be renamed to bryan.old
Now do this, Start>Settings>CP>Network. In the window titled "Primary Logon", click on the dropdown box and and select, "Windows Logon". Follow the prompts to restart.
Now at startup you should get a "Windows Logon" box. Be sure your user name is in the UserName box and leave the password blank. Click on OK. It's important that you click on OK and not Cancel.
Now after it's restarted, restart again to be sure you don't get the logon box any longer.
Let us know what happens.