I have created Hyperlink fields in tables several times and they work as expected. Then, today, I created a hyperlink field in a different table which won't work properly. When I add it to a form, I cannot neither drag and drop into the control, nor select a target object with the Edit the Hyperlink. The control just remains blank. I am totally baffled by this problem. Yes, the form control is Enabled and it is not Locked. I have tried deleting the control and recreating it several times, to no avail.
Is there something in this table configuration that is messing with the hyperlink?