Hey Fred, sorry..
I tried entering
Left([ControlName],1) In ("A","B","C","D")
substituting the "ControlName" with the field name (DrawingNo). This
however gave me several error messages, so I am still confused.
I know I would be entering data on the form, but I didn't want to make
the validation property part of the text box (as I thought you thought
I was trying to do), I wanted it to be a property of the field.
Shall I guess what the error numbers/messages are?
Probably that you can't enter a letter in a field that is designated
as Number datatype.
If DrawingNo is a Number datatype, you can NOT enter any letter in the
field, period!
If the DrawingNo is Text datatype, then perhaps you can let us know
what the error messages are.
I assume your dataentry is something like "A2345", "C9876", etc.
If you place
Left([DrawingNo],1) In ("A","B","C","D")
in the field Validation rule property, it should work (if the field is
Text datatype). It works for me.
Use a form for data entry, always. After you add the validation rule
to the table field, add the field to the form, using the field List
tool button.