Another note. I'm sure it happened a lot of times for somebody who has worked on a Windows Server. You can't log in because the terminal service allows only 2 connections. Error message is: "Terminal Server has exceeded the maximum number of allowed connections." This happened to me when my Windows XP crashed while RDP'd to one of our servers. Problem is I can't log in again to that particular server. Here's what I did in command line to end my session remotely so I can log back in.
Try the following command from your local machine. If 'query' command isn't working, you can try logging in to another server or machine that has 'query' command enabled, then do the following...