Export your OpenPGP key from OpenKeychain as an Autocrypt setup message. Send the setup message to your desktop email and download the attachment. In Thunderbird, go to Account Settings > End-to-End Encryption for your account and select OpenPGP Key Manager. Use File > Import Keys from File to import the downloaded Autocrypt file. This should prompt you to enter the passphrase and complete the import.

Thanks for the reply but i already tried that. It doesn't even recognize the autocrypt-setup-message file as a GnuPg file and says 'Error! failed to import file'. i tried to add the autocrypt Thunderbird-addon but it's not compatible with the current Thunderbird version.

Henry Thomas said

Export your OpenPGP key from OpenKeychain as an Autocrypt setup message. Send the setup message to your desktop email and download the attachment. In Thunderbird, go to Account Settings > End-to-End Encryption for your account and select OpenPGP Key Manager. Use File > Import Keys from File to import the downloaded Autocrypt file. This should prompt you to enter the passphrase and complete the import.

Thunderbird isn’t automatically recognizing the Autocrypt setup message for import. Here are a few steps you can try to manually import your OpenPGP key:

🔹 Check File Extension – Ensure that the exported Autocrypt file has the correct extension (.key or .asc). If Thunderbird isn’t opening it directly, you might need to import it manually.

🔹 Manual Import in Thunderbird 1️⃣ Open Thunderbird and go to Tools > OpenPGP Key Manager. 2️⃣ Click File > Import Public Key(s) from File. 3️⃣ Select the Autocrypt file you exported from OpenKeychain. 4️⃣ Enter your passphrase when prompted.

🔹 Use OpenKeychain to Export Manually If the Autocrypt setup method isn’t working, try this alternative method: 1️⃣ Open OpenKeychain on Android. 2️⃣ Select your key and tap Export. 3️⃣ Choose Export as File (ensure it includes the secret key). 4️⃣ Transfer the file to your desktop and import it in Thunderbird via OpenPGP Key Manager.

If Thunderbird still doesn’t recognize the file, try renaming it to something.asc and then attempt the import again.

Hope this helps!