Oh, Norton is so annoying...
I had a phone call with them a few weeks ago and they ensured me that the problem was resolved, but apparently it's not.
I personally would really recommend not using that antivirus (not just because it's crippling my apps).
I don't have Norton installed (and will never in the future) so I can't see if you can actually recover it - I would assume you should be able to "unquarantine" it.
If that's not possible, the "data.db" file is the database file and located under user/YOURUSERNAME/Library/Containers/WorkingHours/Data. Make a backup, then reinstall the app, then place the file back to that location