GPGMail: error message - unusable key

Jerry McCoy's Avatar

Jerry McCoy

06 Apr, 2018 03:19 PM

I'm using GPG tools suite and when composing an email I get the following error message:

gpg: D19821141808C6AAE993B78A7EAEAD5106DC3F30: skipped: Unusable public key
gpg: [stdin]: encryption failed: Unusable public key

What does it mean? And what do I do about it?

  1. Support Staff 1 Posted by Steve on 17 Apr, 2018 10:38 PM

    Steve's Avatar

    Hi Jerry,

    welcome to the GPGTools support platform. Sorry you are having problems using GPG Suite.

    Let's check if your key is ok:

    1. open GPG Keychain
    2. double click your sec/pub key
    3. search for "Validity" in key tab and post the value to your discussion
    4. search for "Validity" in subkey tab and post the value to your discussion

    Should your key have expired, please re-new the expiration date in the key tab. To renew the subkey, click the cogwheel icon in the subkey tab and update the expiration date.

    To test the change, send a signed and encrypted test email to yourself. Are you able to decrypt and verify the signature successfully?

    In case your key resides on the public key servers, don't forget to upload your updated key, so that the changes are reflected there as well.

    We have open tickets to address this problem. Ideally GPG Keychain and GPGMail would be more pro-active about expiring keys and inform users ahead of the expiry date and explain how by extending the expiry date the key can be used in the future.

    Best regards,

  2. 2 Posted by Jerry on 18 Apr, 2018 03:16 PM

    Jerry's Avatar


    Thanks for this. When I checked validity of the keys I use were all labeled "Ultimate," and the expiration dates were okay.

    But the subways -- when I had never noticed before -- were out of date. When I changed the expiration dates, everything started working again.

    I agree it would be helpful for some notice about expiration dates and make sure users are aware of the subkeys as well.

    Thanks for your help.


  3. Support Staff 3 Posted by Steve on 18 Apr, 2018 03:21 PM

    Steve's Avatar

    Perfect. Glad, this is solved for you. I'm closing this discussion. Should you need further assistance or have questions you can re-open this discussion here or open a new one any time.

    And believe me, this key expiry issue is a priority item we are looking into.


  4. Steve closed this discussion on 18 Apr, 2018 03:21 PM.

Comments are currently closed for this discussion. You can start a new one.

Keyboard shortcuts


? Show this help
ESC Blurs the current field

Comment Form

r Focus the comment reply box
^ + ↩ Submit the comment

You can use Command ⌘ instead of Control ^ on Mac