After being guided here to set my worksheet as i wanted, additional modifications have caused me some problem. At first, i set my table in a way that Cell M4 can only be filled when cell L4 is filled. In the same way, cell M5 can only be filled when cell L5 is filled. The same was done for cells L6:M6 to L18:M18. If the L column cell is not filled, M column cell will be not selectable; But now, it does not work that way, maybe due to additional codes that i have added. Whenever i protect the sheet and fill in L4, when i press tab to go to M4, it tells me "Unable to set the Locked Property of the Range Class". Please help me. Thank You.