...the problem is when the RoomNo is reserved and when you click the Reserve button again with the same RoomNo it will be reserved.... all i want is when you click the Reserved button and the RoomNo is already reserved a msgbox will appear and say "Room Number is already Occupied Please choose another Room"...and the RoomNo that is already will be deleted in the Combobox where you can choose room to be reserved..and i dont know what codes do i need to put in Change Room button....pls help..i needed this program to be fix so bad....PLS HELP!

First your database just contain user table only.
I suggesting you to make complete your database.
It useless when your database is not completed.