I have an IWP-hosted database that keep generating the error message "Portal Related Record Contents Have Been Modified" when there are two users working simultaneously. They are both verifying the contents of records displayed in a portal. The individual records have a user account name field and the TO relationship behind the portal requires this field to equal the users account name, so each user only sees records they are supposed to check and verify. They never see or edit each other's records. Each portal row has a button "Verify" which they click, and it runs a script that sets a field in the record displayed in the portal row. They cannot enter any other fields displayed in the portal rows. Yet they interfere with each other, generating the above error message and often hanging up the database requiring it to be closed and restarted.

This is FMSA 11 running on Snow Leopard.

Anyone know exactly what FileMaker Server is keeping track of here and why it causes a conflict? What's a good way to avoid this conflict, while still using portals?

Are they viewing the portal from the same parent record?

No, we're using a Viewer table, so each user is on their own record.

This may not solve the problem, but there is a fundamental requirement for successful IWP ... that there be one-and-only-one "instance" of a field on a layout; otherwise, all occurrences of the same field must be "populated" in order for data to be Committed.

It's a bit obscure in FileMaker's Help, or at least it could be better emphasized. It's dogged me enough, though, that it's now what I check first when having problems with IWP.