Prevent entering data a second time onto a acess 2010 table

[Sanjo]

I have a simple data entry form where I can key the "row", "COLUMN", SPACE "a" and space "B" onto an access 2010 table. Is there a way that if I key the same four fields, e.g., A5AB that I get a message back before updating telling me that combination already exists?

thanks in advance for any help you can give.

I do generate a calculated data field, which in this case would be "a5ab" and which is displayed on report screens. Could the value of this calculated field be stored on the Table and be used to prevent the same value from again be entered on the Table?

 

[Tooom]

Hi maybe try this.... on the table you are sending the data to and with the column in question selected.

Go Table tools>Fields and tick Unique shown in attached pic

 

[Sanjo]

thanks Tooom, but that isn't working..