Then you need to do a check in the OnConnect event. First load the file, then check if the username is found in that file.
If not, ban that username.
-Create an empty LPR file and store that in your include directory
-Add the file name to "general includes" in addonsused.lpr
-Use the code below, to fill the empty LPR file you have just created
CatchEvent OnConnect( $userName ) # Player event
OnConnect_License();
EndCatchEvent
Sub OnConnect_License() # Player event
### Load usernames from file license.txt ###
UserGroupFromFile( "X", "./../license.txt" );
### Check if username is found in group X ###
IF ( UserInGroup( "X",GetCurrentPlayerVar( "UserName" ) ) == 0 )
THEN
PrivMsg( "^7Banned for breaking the rules too many times" );
cmdLFS( "/ban " . GetCurrentPlayerVar("Username") . " 14" );
ENDIF
EndSub
.. in the path to the license file, means you go up one directory from the current (which should be the includes folder) directory.
Of course you could put the license.txt in the includes folder as well.
14 means the player is banned for 14 days, of course you could set that to a higher value.
I think 999 days or 9999 days is the maximum (but you should check that, or maybe someone knows the maximum value)