MuseScore doesn't start anymore, as there's another one still running in the background

• Mar 26, 2021 - 19:28
Reported version
S3 - Major

I wanted to change the length of multiple half notes by selecting them and clicking on quarter note, so that all are set to this length. The notes were in multiple voices (1 and 2). It was an imported midi file for which the quarter notes were imported as half notes with staccato dots. The midi was imported into MuseScore in November of 2018 (one of the latest versions at the time), saved as project (mscz) and reloaded now with MS 3.6.2. When I clicked on the quarter note symbol with the notes selected, MuseScore crashed and now it doesn't start. Yesterday, exactly the same happened, but MS started again after rebooting the PC. Today, even after rebooting the computer MuseScore doesn't launch.

Trying to launch it from the terminal, I see the following output:

(base) luiz@luiz-Aspire-V3-772:[~/Downloads]: ./MuseScore- 
(base) luiz@luiz-Aspire-V3-772:[~/Downloads]: 

After accessing the shared library it immediately stops loading and it gets back to the input mode on the terminal.

OS: Ubuntu 20.04
Using Jack integrated with Pulse Audio and ALSA.


Status active needs info

The library messages are normal and informational only. Try moving the file that triggered the crash elsewhere then restarting - probably it is crashing trying to reopen it. If that doesn't help, try reverting to factory settings by adding the "-F" option. if you continue to have problems, please ask for help point the Support forum and include more information, including the score you were working on.

Status needs info active

Thanks, the -F option didn't work either, it just crashes before getting into resetting anything. I'll try moving files around to check...
(I didn't choose to set to"active" again, it was selected by default, sorry)

Severity S1 - Blocker S3 - Major
Status active needs info

I found out, there was still a process MuseScore running (I had already closed one) and I had to close it before trying to start again. Launching normally didn't work – begun to freeze on attempting to restore session, but at least I could start with the -F option and now it is running. So, the problem with crashing on changing lengths from multiple notes remains. I'll submit the score in the Support forum.

Title MuseScore 3.6.2 crashed and doesn't start anymore MuseScore doesn't start anymore, as there's another one still running in the background
Frequency Once Few
Regression Yes No
Status needs info active
Workaround No Yes

Yep, I've seen that happening too, quite often actually and since long (to if it is a regression, it is not a recent one).

You can have only one MuseScore (of the same major version) running at a time, that much is by design.

The bug is that sometimes MuseScore doesn't completly terminate and that then (as a workaround) you'd need to kill it manually (like via Windows Task Manager).

A possible fix would be to make a newly started MuseScore to a) report that other process and b) allow to kill it (similar to the installer).
Or of course fully investigate why and under what circumstances MuseScore doesn't completly terminate and fix the root cause.

Yes, these possible solutions sound good! For the possibility b) allow to kill it (similar to the installer), there should be a question dialogue though to avoid accidentally killing an instance that is running fine.