Strange date error in IWP
I am seeing some bizarre behaviour in a database accessed via IWP that doesn't happen when the same db is accessed via Filemaker.
The layout in question has a portal that lists the sessions at an event. The portal is filtered to show a subset of the related records. Two buttons on each row of the portal allow the user either to Reserve a place for the session or Cancel a previous reservation. When used in IWP any attempt to use either button throws up an error message:
"Data Entry Error:
Your attempt to save changes to the current record or request failed because of the following:
Invalid date value in field "SessionDate.""
Needless to say, there is nothing wrong with the date: the Filemaker version is quite happy with it.
The IWP version will stop throwing up the error under two circumstances. First, if I search for invalid dates in the field using the ? character it finds none but thereafter one can edit using the buttons (weird when you think about it). This remains the case until you change the portal filter, when the problem returns.
The second method is to turn off the portal filtering altogether, and the problem disappears.
So the problem appears to be something to do with portal filtering. The field on which I'm filtering has nothing directly to do with the SessionDate field that's ostensibly causing the problem (it's not a date, and it lives in a different, though obviously related, table).
Any clues? Thanks in advance.