Close sqlserver connection, but using sqlquery commands, hard to explain

I would like to close a sqlserver connection, but using sql query commands. What I need to do is close a connection from a steal user password account.
this is the scenario:

I made a system where every password can only run one at the time, so you can not run the application in two or more computer using same password.
So, if when you try to run the app using your password and the system give you a message error about that another user is already working with same password, you can have the option to close the another user's connection, doing that the system can give you access and only one account(password) should be working at that time.

This is because I sold this system base on password's Qty: 1-5, 6-10,...

I can not handle this in a table of user that are active because if for some reason one active user turn off the computer the record is going to be active all the time.

this close connection must be at SQL Server level, so when the "thief" user try to connect get a connection error.

thanks in advance for your help,
Edward

.NET Development7

Hi,

you are probably better off asking this in one of the SQL Server forums. You will probably get more replies there.

Mark.