Sync is broken after ownCloud update

[hannesa2]

After I updated #41165 to recent 10.13.4.1 I see on my Mac few minutes "Sync Activity errors" popping up, in Mac ownCloud client shows me this

and in owcloud .log I see

{
  "reqId": "88f173d6-f969-4a2c-84b5-58d99b0e85d9",
  "level": 2,
  "time": "2024-01-31T11:14:59+00:00",
  "remoteAddr": "111.222.333.444",
  "user": "hannes",
  "app": "no app in context",
  "method": "PROPFIND",
  "url": "\/owncloud\/remote.php\/dav\/files\/hannes\/privateDok\/Filename.jpg",
  "message": "Could not decrypt the private key from user \"hannes\"\" during login. Assume password change on the user back-end. Error message: Bad Signature"
}
{
  "reqId": "7939feaf-89de-4953-857b-1e0df05ecb2e",
  "level": 2,
  "time": "2024-01-31T11:29:35+00:00",
  "remoteAddr": "111.222.333.444",
  "user": "hannes",
  "app": "core",
  "method": "POST",
  "url": "\/owncloud\/index.php\/apps\/oauth2\/api\/v1\/token",
  "message": "Login failed: 'xdXOt13JKxym1B1QcEncf2XDkLAexMBFwiT9j6EfhhHFJhs2KM9jbjTmf8JBXE69' (Remote IP: '111.222.333.444')"
}
{
  "reqId": "c5a4eecf-6b36-4d89-9a93-a25ff3c49610",
  "level": 2,
  "time": "2024-01-31T11:29:35+00:00",
  "remoteAddr": "111.222.333.444",
  "user": "hannes",
  "app": "no app in context",
  "method": "PROPFIND",
  "url": "\/owncloud\/remote.php\/dav\/files\/hannes\/",
  "message": "Could not decrypt the private key from user \"hannes\"\" during login. Assume password change on the user back-end. Error message: Bad Signature"
}

But I can login on web site with my known password !
Does someone has an idea, what's wrong here after the ownCloud update ?

[iasdeoupxe]

Could be not ownCloud update related but rather relevant that the underlying operating system got updated to a more recent version (as indicated in / via the PHP version message in #41165 (comment)) with an update jump from OpenSSL 1.x to 3.x while using the encryption app.

There seems to be a note about OpenSSL versions here:

https://doc.owncloud.com/server/10.13/admin_manual/configuration/files/encryption/encryption_configuration.html#general-notes

leading to the following with an important note about OpenSSL:

https://doc.owncloud.com/server/10.13/admin_manual/installation/manual_installation/manual_installation_prerequisites.html#openssl-version

[hannesa2]

In the meantime I got one step further by 'filelocking.enabled' => false,

I see, when ownCloud needs older stuff, only docker is the way to got

[iasdeoupxe]

If there is no external storage (means storage hosted on a different, external system) attached to this system i would even disable encryption as this is pretty useless on systems having the files only stored on the same system ownCloud is hosted at:

https://doc.owncloud.com/server/10.13/admin_manual/configuration/files/encryption/encryption_configuration.html#general-notes

The primary purpose of the ownCloud server-side encryption is to protect users’ files when they’re located on remote storage sites, such as Dropbox and Google Drive
...
Encryption keys are stored only on the ownCloud server, eliminating exposure of your data to third-party storage providers. The encryption application does not protect your data if your ownCloud server is compromised, and it does not prevent ownCloud administrators from reading users’ files.

[hannesa2]

In the meantime I got one step further by 'filelocking.enabled' => false,

The second thing was, I moved local the content of an consumed share. But the message was not clear to me.
It works now

[iasdeoupxe]

I would still disable encryption, it doesn't provide any security benefit and just adds complexity to your setup less people are able to give support for :-)