Local backup continuously fails

[rettungsboje]

Guidelines

• I have searched searched open and closed issues for duplicates
• I am submitting a bug report for existing functionality that does not work as intended
• This isn't a feature request or a discussion topic

Bug description

I try to use the local backup feature.
It fails after a few percent, showing the notification "Backup failed", "Your backup contains a very large file that cannot be backed up. Please delete it and create a new backup". Clicking the notification does nothing. Signal provides no way of finding that suppodedly very large file, whatever that may mean.
Also, disabling and re-enabling backups results in the same issue.

Screenshots

Device

Pixel 8

Android version

16

Signal version

7.70.2

Link to debug log

No response

[greyson-signal]

Hi, are you able to post a link to a debug log?

[Genis-Sage]

you can go to settings - Data and storage - manage storage - review storage

there you see the files, sorted by size

[rettungsboje]

@Genis-Sage this did the trick. thanks.

i apparently tried to send a 3GB video a few months ago, which failed. but signal had stored it since then.

review storage let me find and delete it.

[rettungsboje]

very confusing how there is a file size limit and also how users are not hinted towards the (large) file in question

[rettungsboje]

This issue also applies to account transfers.

Prior to deleting the 3GB file, I tried account transfer to a new phone. Failed, without explanation. Now it works.

[greyson-signal]

The error is a bit of a red herring. We do hit that error when the backup process indicates we're trying to write a large file, but the most likely cause of us thinking we're trying to write a large file is that, for some reason, the stream is malformed. If you could please supply a debuglog, that may give us some more info.

[rettungsboje]

https://debuglogs.org/android/7.70.2/d80e71a6451b249bc428897af9306db260e516268feb2af315ecee79ce03a6fa

[greyson-signal]

Looks like you have some successful backups in there? The most recent one seems to have completed just fine. I do see the errors on earlier backups, and unfortunately nothing sticks out as the cause :/