if [combobox] is empty then msgbox - not working

[MayoRR5]

Just to follow up I created a form to act like a message box displaying the error message.

I then added an uncontrolled textbox on the mainform to mirror the control in the subform and it recognises when no entry is made against this new textbox.

 

[nanscombe]

I have tried to recreate how I believe this part of your system works.

When you double click on the textbox ISO Revision it checks to see if the combo box Qualtype has a value in it.

The thing about the sub form is that the first record will always be selected so it will only fail if:

a) QualType has not been filled in
b) The cursor is deliberately placed on an empty record in the sub form
c) No record has been added to the subform.