https://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=13171 --- Comment #14 from Barton Chittenden <barton@bywatersolutions.com> --- Katrin, I believe that what's happening here is that when rows are deleted from the letter table, there's a cascading delete on message_transports. There's a foreign key relationship between letter and message_transports, but the keys aren't entirely constrained... so deleting *any* row in the letter table will delete the rows in the message_transports with that letter code. At the time that this was discussed, this wasn't seen as a big deal, because the only way this could happen through the GUI was to delete the entire message, in which case the row would need to be removed from message_transports anyway. Unfortunately this didn't take upgradedatabase into account, and I think that we've seen this happen a couple of times because of that. --Barton -- You are receiving this mail because: You are watching all bug changes. You are the assignee for the bug.