Comment 2 for bug 430964

Hi,
Thanks for trying Ubuntu One!

The issue seems to be related to broken metadata. (possibly caused by an old version of the client)

As you already deleted all the files, the actually fix/workaround would be delete also syncdaemon metadata, as it looks like it's broked in some way, to be more precise the shares/shared folders metadata.

The metadata is located at: ~/.cache/ubuntuone/syncdaemon/
please do a backup of it and then: rm -Rf ~/.cache/ubuntuone/syncdaemon/

I'll work on a fix to discard broken metadata during metadata migration.

Regards,