I need help writing a code that prevents moving to a new record if two different text boxes are null. I also need the code to put “Yes” in a text box once those two text boxes aren’t null.

Have identical problem. 1 specific field CANNOT be Null or 0 (zero).
I hoped by doing a test on this field and adding a "setfocus" instruction that m cursor should return/stay in this field until a value was put in.
Instead the cursor moves tot the next field.
Thanks for any idea.
Marc