Larry -
Did you just recently make a change to that form?

Run down the Troubleshooter
It possible that the db got corrupted somehow.
First an foremost make a backup copy of your database as it is right now (even though it has errors).


Copy your latest backup to a new "test" folder and run it.  Does the button work there?

I have had a similar issue with my data base.
I have a drop down box which I have added a VB code to clear the box when it has lost focus. This works well for awhile and then out of the blue for no rhyme or reason it throws up the same code.
To fix it I open up the VB  Editor, and type  something in, delete it, close it and all comes good.
I would suggest that if it is anything to do with the Macro, then open it save it and try again. That way you do not lose any of your work.
Make a copy and play with that first.

Thank you for your recommendations.