Recover Key setup after OS upgrade

[Chris Wensink]

I have a user who just upgraded from Windows 7 Pro to Windows 10 Pro, using Thunderbird and the Enigmail / gnupg tools for sending encrypted emails. Prior to the upgrade I backed up his entire User profile directory to a backup server, then did a fresh install on the same hardware of Windows 10 Pro. I then set up his Thunderbird / Engimail in the same way as before, he knows the pasphrase to unencrypt emails, I've set up a new certificate / key and revocation key, send his public key to the other encrypted users, and they imported the new public key. New emails now come through from other users to him encrpted, and work just fine, however old emails that were encrpted are throwing an error saying key not found.

I have a backup of the entire c:\users\<username> directory from the old system, so I need to know where the old key files are stored so I can copy those back into the new Thunderbird Profile directory so that old encrypted emails can be read again, and the history of those emails is not lost.</username>

I also have the saved public keys from other users and the old revocation key, and a key for his own username saved in a mapped network drive.

I've imported all those keys back into the profile, but there are three lines of keys that are grayed out and listed as revoked, and he still cannot open old encrypted emails. How do I restore the ability to read old encrypted emails?

Chris

[Olav Seyfarth]

Hi Chris, Keys are stored by GnuPG, thus not in %AppData%\Thunderbird but in %AppData%\GnuPG :-) Olav

[Chris Wensink]

Olav,

Is it safe to just copy the contents of the old directory into the new one, or will that destroy the updated keys?

[Patrick Brunschwig]

That will destroy the updated key(s).

[Olav Seyfarth]

Yes, but it is possible to export/import. I recommend this:
1. export your current (new) keys, public AND private
2. double check the results (text files, readable headers)
3. move the new GnuPG folder aside (like GnuPG.NEW)
4. copy the old GnuPG folder there instead
5. check old key setup is fine, optionally backup to files
6. import the new keys from the above exported files
7. set trust to the new keys

[Chris Wensink]

Thanks for the steps, I'll give that a try!