Context: We just killed the Molten Alliance bosses and looted our respective daily chests and the big chest.
And after hitting the “ready” button to return to the lab, the game gave to me, and only to me as the instance creator, the following error:
“InstanceCreated failed. Error=42; Product=5; Module=18; Line=289”
After that a couple of mobs respawned but other than that, after hitting the manual return to Dessa’s Lab button, it all went well.
Hope it helps!