I have multiple Nextcloud instances (company and clients). When testing the sync client with a new client deployment I cannot complete the setup stage “Add Folder Sync Connection”, with the error as per subject (and see screenshot below). The same desktop client is happily working with a different Nextcloud instance.
The web UI works fine for the user account.
So far have tried: deleting and recreating the account (both on the desktop client and on the Nextcloud instance) and upgrading the client (was still the Owncloud branded one) and checking with an early adopter from the client that the desktop sync is working for them.
Differences between the server with which the desktop client works and the one that doesn’t: working instance uses internal auth and is a single server installation, the other uses LDAP/AD and is multi-server.
Additional:
“Create Folder” works, but then the error message returns and the folder isn’t available to choose as a target;
the desktop app correctly reports the amount of data in use by the test account on the server.