Steve on 02 Sep, 2018 05:41 PM
welcome to the GPGTools support platform. Sorry you are having problems using GPG Suite.
The error message you are seeing is caused by an expired key of yours. To prevent this situation in the future we just recently implemented a mechanism to inform users about keys that are about to or have expired.
Could you please download and install our latest hotfix GPG Suite. You should then see a dialog after opening Mail.app (with GPGMail) or GPG Keychain. The dialog will ask if you want to extend your key. Just select yes and you should be back in working state.
Please let me know if that worked as expected.
All the best,
Disclaimer: This is a development version which has not been thoroughly tested yet - bugs or crashes are to be expected. Thanks for helping us test.