"JFAZ" wrote...
I want to force users to complete a cell if they have previously completed
a
cell. This is to stop incorrect data being submitted to an interface
table.
I have tried validation and found ways of validating data input but not
forcing an entry if the cell is left blank.
Any help would be welcom

How are these data being submitted to this interface table? If by macro,
then all you need to do is add logic to that macro to check for necessary
entries. If there are any missing entries, display an error message stating
which cells contain invalid entries and that no data was submitted.