Sign out of your account, then go into the Pervasive Monitor and see if it shows you connected. If so, delete your connection.
 
 
Start Pervasive Monitor and go to Options > Connect to login to your server
 
Then go to MicroKernal > Active Users to see usernames of those logged in
 
There is a button for disconnecting all users (don't use that one) and one for removing a single user. Highlight the user to disconnect and send them into the ether.  
 
Kicking everyone off and rebooting the server works, too. =)