Fine tuning Thunderbird's end-to-end encryption

2022-08-04 2-minute read

I love that Thunderbird really tackled OpenPGP head on and incorporated it directly into the client. I know it’s been a bit rough for some users, but I think it’s a good long term investment.

And to demonstrate I’ll now complain about a minor issue :).

I replied to an encrypted message but couldn’t send the response using encryption. I got an error message indicating that “End-to-end encryption requires resolving certificate issues for” … and it listed the recipient email address.

“Screen shot of error message saying: End-to-end encryption requires resolving certificate issues for [blacked out email address]”

I spent an enormous amount of time examining the recipient’s OpenPGP key. I made sure it was not expired. I made sure it was actually in my Thunderbird key store not just in my OpenPGP keychain. I made sure I had indicated that I trust it enough to use. I re-downloaded it.

I eventually gave up and didn’t send the email. Then I responded to another encrypted email and it worked. What!?!?

I spent more time comparing the recipients before I realized the problem was the sending address, not the recipient address.

I have an OpenPGP key that lists several identities. I have a Thunderbird Account that uses the Identities feature to add several from addresses. And, it turns out that in Thunderbird, you need to indicate which OpenPGP key to use for your main account… but also for each identity. When you drill down to Manage Identities for your account, you are able to indicate which OpenPGP key you want to use for each identity. Once I indicated that each identity should use my OpenPGP key, the issue was resolved.

And here’s my Thunderbird bug asking for an error message pointing to the sender address, not the recipient address.