Cannot synchronize with filesystem: No such master key

[piotrek-k]

tl;dr: My existing notes cannot be synchronized from Filesystem sync target

Hello,

I'm setting up a new Joplin instance. I want to import my existing notes. Here is an error that I see after specifying path to my notes:

Completed: 30/10/2022 14:59 (148ms)
Last error: Error: No such master key: fd68c0bcbfc14a0e80b677316e1bb8e1

There is also an error in console in Dev tools:

Logger.ts:219 14:59:45: Synchronizer: Error: No such master key: fd68c0bcbfc14a0e80b677316e1bb8e1
    at setMasterKeyHasBeenUsed (node_modules/@joplin/lib/services/synchronizer/syncInfoUtils.js:300)
    at Synchronizer.<anonymous> (node_modules/@joplin/lib/Synchronizer.js:434)
    at Generator.next (<anonymous>)
    at fulfilled (node_modules/@joplin/lib/Synchronizer.js:5)

My notes are not encrypted. Isn't term "master key" connected to encryption feature? Might it be that Joplin tries to decrypt my notes?

Environment

Joplin version: 2.8.8 (prod, linux, flatpak)
Platform: Linux desktop
OS specifics: Ubuntu 22.04

Steps to reproduce

1. Install Joplin
2. Set sync to Filesystem sync, provide path
3. Click "Synchronize"

Logfile

joplin_logs.txt

[laurent22]

They have never been encrypted?

[piotrek-k]

Might be that I've tried this option a few months ago, but since then I've worked on unencrypted notes. I can see right now that all my notes on filesystem are plain text

[wh201906]

This problem might be similar to this one
https://discourse.joplinapp.org/t/error-no-such-master-key-new-install-on-ipad/27308

[laurent22]

Yes, probably. You can delete the "activeMasterKeyId" block in info.json to solve the issue. I don't quite understand how there can be a key ID there when there's no master key, but I'll add a fix to better handle this anyway.

[wh201906]

Is it necessary to backup the sync target directory first then modify the info.json?

[laurent22]

No, it's relatively safe to modify info.json. Just to be sure, you might want to keep a copy of the original info.json

[piotrek-k]

Thank you, deleting "activeMasterKeyId" solved my problem.