[MU4 Issue] MSCZ files corrupted beyond repair, because of corrupted ZIP file

[cbjeukendrup]

Describe the bug
A few times per month, someone somewhere in the world reports a file corruption where the ZIP container file has become corrupted, so that nothing of the contained score can be saved.

This has been the case for years now, and it is exactly the same in MS3 and MS4 for years now.

The problem exists in several variants:

1. the saved MSCZ file is completely empty, i.e. 0KB
2. the saved MSCZ file contains only zeros, no real data
3. the saved MSCZ file contains seemingly random data
4. the saved MSCZ file still looks a bit like a ZIP file but is still corrupted so that one or more files from it can't be read

In this issue, we will collect cases of this. When adding a case, please make sure to add the following information:

• OS (Windows, macOS, Linux) and OS version
• MuseScore version in which the file was saved the last time
• Filename under which the file was saved
• A link where the file in question can be downloaded, or at least a clear description which of the variants mentioned above is applicable

Please keep comments clear and concise, and don't use this thread for long back-and-forth conversations, to avoid making it longer than necessary.

[cbjeukendrup]

For example:

Original report: #15113
OS: Windows
MuseScore version: 4.0.0.223362132 / d050fb0
Filename: unknown
The file: corrupted_file.zip
Variant: contains only zeros
Additional info: the backup file was affected too

[cbjeukendrup]

Original report: https://musescore.org/en/node/342465
OS: Windows 10
MuseScore version: 4.0.1
Filename: C:\Users*********\Documents\Musescore4\Scores\KONZERT_gdur.mscz
Variant: 0KB

[cbjeukendrup]

Original report: https://discord.com/channels/818804595450445834/818804809784229898/1057744302765256874
OS: Windows 10
MuseScore version: 4.0.0 / 5485621
Filename: Figaro.mscz
Variant: corrupted zip file; could be (partially?) repaired using zip -FF
I'm not allowed to upload the file here, unfortunately, since it was sent to me privately

[Jojo-Schmitz]

See also https://musescore.org/en/node/271185 and the many "What links here".
And also https://docs.google.com/forms/d/e/1FAIpQLSetNNORplB9K7ye_qicnchXIhQ_GK_vYIwWF5TwNaPtqOB8Iw/viewform
which had been setup to collect those reports, no idea where they ended up though

[Jojo-Schmitz]

See also #16334

[cbjeukendrup]

Original report: #16273
OS: Windows 10
MuseScore version: 4.0.1
Filename: 降E大调华丽圆舞曲.mscz
Variant: corrupted zip file; only the main mscx file cannot be read, and zip -FF cannot change anything about that
The file: scores.zip
Additional remark: I have seen exactly this kind of corruption before, where only the main mscx file got unreadable. This was sent to me privately so I cannot upload it here. In that case the filename didn't seem to contain any special characters so I don't think those are the cause of the corruption.

[cbjeukendrup]

Original report: #16382
OS: Windows 10
MuseScore version: 4.0.1
Filename: "C:/Users/pmerkus/iCloudDrive/10 Bolero.mscz"
Variant: contains only zeros
The file: 10 Bolero corrupt.zip

[cbjeukendrup]

Original report: https://discord.com/channels/818804595450445834/818804809784229898/1076199931674644490
OS: Windows 10, 22H2
MuseScore version: 4.0.1
Filename: The_Free_And_Infinite_Stars1.mscz
Variant: contains only zeros
The file: https://cdn.discordapp.com/attachments/818804809784229898/1076199956282605568/The_Free_And_Infinite_Stars1.mscz

[Jojo-Schmitz]

Please also check the 2 scores from https://musescore.org/en/node/345595

[cbjeukendrup]

It seems we haven't had any similar reports anymore for some time, but to be honest I'm not monitoring MuseScore.org very actively. @Jojo-Schmitz and @MarcSabatella, you certainly have a better idea of the situation; are we indeed no longer getting reports about this, or still?

[Jojo-Schmitz]

We still do, unfortunatly, on a daily basis

[cbjeukendrup]

Too bad... Could you collect some of these and link them here? The more data we have, the more likely we'll find a pattern.

[Jojo-Schmitz]

Latest ones:

• https://musescore.org/en/node/363305
• https://musescore.org/en/node/363238
• https://musescore.org/en/node/363119
• https://musescore.org/en/node/345871#comment-1235385
• https://musescore.org/en/node/363045
• https://musescore.org/en/node/347299#comment-1234471