Apple Mail 8 shows welcome screen on every launch I recently upgraded from Lion to Yosemite. Now using Mail 8.2 the welcome screen shows up with every launch of the program. Dis- and reenabling the IMAP account like proposed here did not fix it. What can I do?
As there were no other suggestions, I fully deleted ~/Library/Mail/V2 as well as ~/Library/Preferences/com.apple.mail.plist, rebooted the system, re-added my IMAP account and had my ~50k mails re-indexed. This took about two hours but now Mail.app behaves as expected (at least in this case).