We're running Qlik Sense Enterprise April 2019 Patch 1 (13.21.2). Periodically, I see reload tasks failing with this error:
System error: Failed to open file in write mode for file: [...].qvd
I've skimmed a few forum posts I've found about that error and seen various things suggested regarding what the problem might be and how to solve it, but I was hoping to narrow the problem down further before taking action.
One big clue I've noticed is that the file in question is locked at the OS level. For instance, if I try to delete, move, or rename it using Windows Explorer, I get the error:
The action can't be completed because the file is open in another program.
I can get my IT department to manually release the lock on the file and everything starts working again. Or they can reboot the server to fix it. This makes me think that this is not just a problem where two Qlik tasks are getting deadlocked, but rather, Qlik is sometimes leaving OS-level write-locks on files indefinitely instead of releasing them.
How can this be remedied?
One other thing I will mention for completeness is that I have been using the EasyQlik QViewer program to look at the contents of QVDs. But I never use that utility to alter QVDs and it never complains about not being able to get locks, so I doubt it's the problem.