Boris

 -- install the addon 'importexportools NG' 
-- highlight the message folder, rightcllck and select importexport option to export mbox 
-- now, highlight Local Folders, rightclick and select importexport option to import

Assuming you mean a gmail account, do this: - check account settings>synchronization&storage and verify that 'synchronize all messages regardless of age' is checked - click file>offline>download to ensure all message content is downloaded - all messages will now be on your PC. if you wish to save separately, then do these steps: -- install the addon 'importexportools NG' -- highlight the message folder, rightcllck and select importexport option to export mbox -- now, highlight Local Folders, rightclick and select importexport option to import - you will now have all messages in local folders and the gmail account can be removed, if desired.