Portal won't all entry of data
I have two portals side by side. They are identical, except for the fields on which the relationships are based. One works fine, the other one gives me the following error when I try to enter data:
"This action cannot be performed, because this field is not modifiable."
I can click on a field, even select the pop-up content, but when I try to move on to the next field, I get the error.
I've checked and double-checked the relationship. The fields use the correct relationship. The fields themselves, in the related file, are just normal text and date fields, not calculations, nothing special, nothing restricting them. In fact, one field is used in both portals; in one it works (allows data entry), in the other, FM says the field is not modifiable.
I'm stumped. Ideas?