If you updated the ownCloud Desktop Client to 7.1 and your ownCloud Server account suddenly stopped syncing, you are not alone — and there is a clean path back.
What changed in Desktop Client 7.0
Starting with Desktop Client App 7.0, the client connects exclusively to ownCloud Infinite Scale. Support for ownCloud Server (also called ownCloud Classic or oc10) was removed in that release. The 7.1 update that shipped shortly after carries the same limitation. If you picked it up through a routine Linux distribution update or a manual Windows/macOS upgrade before the release notes got your attention, your ownCloud Server account will stop connecting as soon as the new client starts.
The key thing to understand: this is not a server-side problem and not a credentials issue. The 7.x client simply does not speak the protocol that ownCloud Server uses.
Why reinstalling 6.x alone does not work
The first instinct is to uninstall 7.1 and put 6.x back. That does not work out of the box because the 7.x client writes its configuration in a format that the 6.x client refuses to open. Launching the reinstalled 6.x client against the existing configuration directory will result in a startup failure.
The good news: the Desktop Client has automatically backed up your configuration directory before each major upgrade for several releases now. Your original 6.x configuration is sitting intact on disk, waiting to be restored.
How to restore 6.x
DeepDiver1975 has written a detailed, platform-specific recovery procedure covering Linux, Windows and macOS — including exactly where the backup lives on each platform and the steps to restore it safely:
The short version: locate the backup the 7.x client created before upgrading, move it into place as the active configuration, then install the 6.x client. Full command sequences and folder paths for each OS are in the linked guide.
Going forward
If you are running ownCloud Server and are not yet planning a migration to ownCloud Infinite Scale, stay on the 6.x Desktop Client line. The release notes on the ownCloud client releases page flag breaking changes — worth a quick read before any major version bump.
For users who are ready to move to ownCloud Infinite Scale, the 7.x client is the path forward. Migration documentation is available at owncloud.dev.
