My client always complain about some file that already configure sync to nextcloud access deny

Dear support team,

I have already running nextcloud version 20.03 and i have configure nextcloud client to sync all file and folder to my nextcloud server and the problem is my client some time when access to file world or excel that already sync to nextcloud server and it show “Access Denied. Contact your administrator” after show that when i reboot PC then i can access back normal.

any idea?

Best Regards,
Kimseng

Your problem sounds like a possible file locking problem to me. Have you installed and configured e.g.Redis to manage the file locking?

https://docs.nextcloud.com/server/21/admin_manual/configuration_server/caching_configuration.html?highlight=redis#id2