[Bug]: Subfolders are recreated constantly

[michel-thomas]

⚠️ Before submitting, please verify the following: ⚠️

• [x] This is a bug, not a question or a configuration issue.
• [x] This issue is not already reported on Github (I've searched it).
• [x] Nextcloud Server and Desktop Client are up to date. See Server Maintenance and Release Schedule and Desktop Releases for supported versions.
• [x] I agree to follow Nextcloud's Code of Conduct

Bug description

Next to #8915 issue, I haven't clients with 4.0.0 version anymore. Clients are with 3.17.x or 4.0.1 version only.

I tried to clean folder structure to purge all duplicates empty folders. But these empty subfolders are recreated every day, by any user.

What I tries to cleanup in a bash script:

1. list all empty folders with find /data/nextcloud/path -type d -empty
2. keep only empty folders that have the same name as parent
3. remove them

I tried 3 methods for removing:

• rm -r subfolder in filesystem, followed by occ files:scan and occ maintenance:data-fingerprint
• occ files:delete -f -q subfolder
• delete manually some folders via web interface

No matter how I remove these folders, they are recreated later.

I asked users to upgrade to 4.0.1, but I also notice there are some empty subfolders that are recreated by users already in 4.0.1…

Not sure, but it seams that reconfigure totally the client (remove all sync config and then recreate conf in a new empty root folder) could solve the problem. But I have more than 1000 subfolders and more than 100 users, so I can't go on every desktop to do so! And users won't understand why.

Another "not sure", but I think recreating these folders is done only by Windows clients.

Steps to reproduce

1. Instance with many empty subfolders named as their parents due to #8915 issue
2. Many users (>100), none with version 4.0.0
3. Try to delete some or all subfolders created by the issue
4. These folders comes back from a user

Expected behavior

Deleting these subfolders should be permanent.

Which files are affected by this bug

1000 subfolders

Operating system

Windows

Which version of the operating system you are running.

Mixed 10 and 11

Package

Official Windows MSI

Nextcloud Server version

31.0.8

Nextcloud Desktop Client version

3.17.x and 4.0.1

Is this bug present after an update or on a fresh install?

Updated from a minor version (ex. 3.16.1 to 3.16.2)

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

Are you using an external user-backend?

• [ ] Default internal user-backend
• [ ] LDAP/ Active Directory
• [x] SSO - SAML
• [ ] Other

Nextcloud Server logs

Additional info

No response

[nilsding]

Hi, could you please create debug archive(s) from the affected Windows Clients and upload them here https://cloud.nextcloud.com/s/KiRSmsP3TNAC2LY ?

[Christian-98]

Hello, unfortunately, I'm also experiencing the same problem on a Nextcloud environment. New, always empty, subfolders are created every day. @nilsding could you tell me how I can enable logs so I can share them with you?

[michel-thomas]

Hi, could you please create debug archive(s) from the affected Windows Clients and upload them here https://cloud.nextcloud.com/s/KiRSmsP3TNAC2LY ?

@nilsding Done. Sorry for the delay, I was too busy. I put 3 logs and some examples, if you need more: I have!

Thanks for your help

[michel-thomas]

could you tell me how I can enable logs so I can share them with you?

@Christian-98 You have documentation here: https://docs.nextcloud.com/server/latest/admin_manual/desktop/troubleshooting.html#obtaining-the-client-log-file

[nilsding]

@michel-thomas thanks for providing the debug archive and extra information, I really appreciate it :)

from what I've seen in the client logs this might be resolved with #9077

[michel-thomas]

Hello. Many thanks for this good news. How can I test this 4.0.2? Is there a pre-release or should I wait its publication?

[michel-thomas]

Hello @mgallien

can you explain why postpone this patch to 4.1.0? I have a production problem, not a serious one (no data loss), but really annoying one.

Thanks

[nilsding]

@michel-thomas the patch was backported to 4.0.2 in #9080 which we will publish today

[michel-thomas]

Hello @nilsding

I have now an example where all users are with 4.0.2 and empty duplicate folders are still recreated every time.

Not sure this is the problem, but 22 folders on 31 that are recreated every time have at least one special character in their path (not necessary in the folder name): é, è, ê, «, », @, (, )…

And 100% of these 31 folders have at least one space in path.

Some path are short (49 characters) and other very long (291).

Unfortunately, I don't have logs for the moment with this group of users. I ask them.