could not add a local database because of an unknown error

With Devonthink Pro Office, 2.8.2

I have an existing database synched using dropbox.

I’m trying to add this database to a new computer. I click ‘Import database’ on the sync tab of preferences, select my dropbox folder, and select my database. At first I get the message:

could not add a local database because of an unknown error.

Now, I get the message “No databases were found”. My dropbox folder still contains a Devonthink folder, with databases and transactions folders.

Best to open a ticket directly with Support for this sort of problem. Include logs and Console messages, if any.