Permission problem when i try to kill an inactive session

Hello, I try to kill an inactive session at the following way:


NombreDatabase.RESET;
IF NombreDatabase.FIND ('-') THEN;

Session.RESET;
Session.SETRANGE ("Database Name", NombreDatabase."Database Name");
Session.SETFILTER ("Idle Time", '>%1', 1800000); //a los 30m se anula la sesion
IF Session.FIND ('-') THEN
Session.DELETE (TRUE);

but when i execute this code, i get the following error:

The following SQL servers error(s) occurred:
6102,"42000", [Microsoft][ODBC SQL Server Driver][SQL Server]. The user doesn't have permission to use KILL command.
SQL: 53

How could i solve this problem? What user must have permission, navision user or sql user? Which is the permission that i must give to them?