Sync 'Couldn't convert to placeholder' for all files

Nextcloud version _(21.0.3)
Operating system and version _(Windows 10)Apache or nginx version _(?)_: replace me`
PHP version _(7.4)

Recently upgraded to 21.0.3 using updater.phar
Upgrade appears successful except sync using client 3.2.4 (Windows) results in 2 red warnings for each file:

  1. ‘Unable to write metadata to database’
  2. ‘Couldn’t convert to placeholder’
    Running occ maintenance:repair resolved 1.
    Warning ‘Couldn’t convert to placeholder’ for each file still occurs

Is this the first time you’ve seen this error? _Y

Steps to replicate it:

  1. Trigger sync

The output of your Nextcloud log in Admin > Logging:


The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

In order to help you as quickly as possible, before clicking **Create Topic** please provide as much of the below as you can. Feel free to use a pastebin service for logs, otherwise either indent short log examples with four spaces:


The output of your Apache/nginx/system log in /var/log/____:


sounds like desktop error related to VFS. did you enable VFS? I hit this once as well - it’s not really clear why it happened but reboot helped in my case.

Virtual Files stopped working Client 3.2.3 · Issue #3495 · nextcloud/desktop · GitHub