I can't understand this. Using Thunderbird 102.15.1 on Windows 10, and the private key was added to its native OpenPGP key manager more than 1 year ago. I have old emails that were encrypted, and Thunderbird was decrypting and showing them to me just fine.
Today all of a sudden, all those emails show up with a red message "The secret key that is required to view this message is not available" ... I then open the account settings, and I see that Thunderbird says "Thunderbird doesn't have a personal OpenPGP key for [email protected]" ... Huh? I know that's false, because I haven't changed a thing, and looking at its OpenPGP Key Manager I can see the key there just fine, like it always was.
The key has not expired (in fact it doesn't have an expiry date) and it was created less than 1.5 years ago.
Tried restarting Thunderbird, also deleted the key and re-added it, etc. Nothing worked.
It gets even more weird:
Two weeks ago I copied the Thunderbird profile folder from Windows 10 to my MacOS machine. At that time, both of them were able to decrypt those emails just fine. I looked at my MacOS and Thunderbird there still decrypts those emails just fine! In the account settings, Thunderbird on MacOS says "Thunderbird found 1 personal OpenPGP key associated witrh [email protected]" ... like the one on Windows used to say, but no longer does. The OpenPGP Key Manager from Thunderbird in MacOS looks exactly like the one on Windows.
I'm stumped. I don't even know where to start looking ... any clues? What in the world could have changed on my Windows to affect this? I know that Thunderbird no longer relies on any external dependencies for PGP encryption since they incorporated OpenPGP natively. Somehow it stopped recognizing its own OpenPGP Key database it seems.
