Use #thunderbird on #linux. Click right on blue email address in left hand column & menu opens. Go to settings - synchronization & storage - selected keep messages in all folders for this account on this computer & in Advanced checked all folders under that email are ticked (except trash and Bulk). Then in menu Help (three-bar icon) - Troubleshooting information - Application Basics table - row Profile Directory - Clicked Open Directory & find all emails. 13GB of which sent is 6GB ! #yahoomail