I used the multiple upload without saving to database and place them in seperate maps. (id number of the record).
On the detailpage I show the thumbnails belonging to a record with the "File List Recordset". This all works well.
When I click on the thumbnail a popup should show up with a larger version of the image but instead of that I get the message "Internal Error. Session expired."
When I go back to the master list and go back to the detailpage with the thumbnails everything works fine. The error shows up only the first time.