[Homesick]

Hi!
This is how OF support staff helped me, and it asumes you have a working sync function and the right OF database in the cloud. So when you follow the procedure bellow, you'll be able to replace the local database with the one on the server...
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On the Mac:
- Quit OmniFocus
- Open this folder: Home > Library > Application Support > OmniFocus

If you are running Mac OS X 10.7 or later the "Home > Library" folder is hidden, so you'll need to hold the "option" key on the keyboard and then select: Menu Bar > Go > Library

- Rename the file "OmniFocus.ofocus" to: "old-OmniFocus.ofocus"
- Launch OmniFocus
- Tap the sync icon in the toolbar
- When prompted to "Replace your database and start syncing?" click "Sync"

If that doesn't work, or if you would prefer, zip up the "old-OmniFocus.ofocus" database and send it in. We'll remove the corrupted zip file and send it back. (In the Finder you can zip up a file by control-clicking the file and choosing "Compress <file_name>".) We take privacy very seriously around here, but totally understand if you'd rather not send it in.
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The help came really fast in my case...