I got an application in the server, client's PC map 'S' as network drive
link to the server,
my system will place in "S:\AcctSystem\"

If that company got 10 PC, they can map the S drive and run the exe easily.
Now, we need to control the license with 5 users which can login the system
I got a little idea
(1) when 1 user login ( increment a field nooflogin in a LoginTable )
(2) everytime user login (I will check the nooflogin , if the number over 5)
, reject user login
(3) everytime user logout the user(nooflogin will be decreased )

Problem : If the user didn't logout very well, ( task manager kill the task
or PC hangs) that will make the no of login incorrect,

Can anyone give me some idea to do ??
Thanks a lot