Mac Mail is a popular email client that is used by many individuals and organizations to send and receive emails. One of the features of Mac Mail is the ability to sign messages with a digital signature. However, sometimes Mac Mail users may encounter an error message that says “Unable to verify message signature”. In this guide, we will discuss what this error message means and what you can do to resolve it.
What Does “Unable to Verify Message Signature” Mean?
When you send an email with a digital signature, the recipient’s email client checks the signature to verify that the message was not tampered with during transmission. If the signature cannot be verified, the recipient’s email client will display an error message that says “Unable to verify message signature”.
This error message can occur for several reasons. One possibility is that the digital certificate used to sign the message has expired or has been revoked. Another possibility is that the recipient’s email client does not recognize the digital certificate used to sign the message.
Steps to Resolve the “Unable to Verify Message Signature” Error
If you encounter the “Unable to verify message signature” error in Mac Mail, there are several steps you can take to resolve the issue. Here are some possible solutions:
1. Check the Digital Certificate
The first step is to check the digital certificate used to sign the message. If the certificate has expired or has been revoked, you will need to obtain a new certificate.
To check the certificate, open the message that you received the error message for and click on the “Details” button next to the error message. This will display information about the digital certificate used to sign the message. Check the certificate to see if it has expired or has been revoked.
If the certificate has expired, you will need to obtain a new certificate. If the certificate has been revoked, you will need to contact the sender to request a new message with a valid certificate.
2. Update Your Mail Application
If you are using an older version of Mac Mail, it may not recognize newer digital certificates. Updating your mail application to the latest version may resolve the issue.
To update your mail application, open the App Store and click on the “Updates” tab. If there is an update available for Mail, click on the “Update” button to install the update.
3. Add the Certificate to Your Keychain
If the digital certificate used to sign the message is not recognized by your mail application, you can manually add the certificate to your Keychain. The Keychain is a password management system used by macOS to store passwords, digital certificates, and other secure information.
To add the certificate to your Keychain, follow these steps:
- Open the message that you received the error message for and click on the “Details” button next to the error message.
- Click on the “View Certificate” button. This will display information about the certificate.
- Click on the “Show Certificate” button. This will display the certificate in a new window.
- Click on the “Install Certificate” button. This will open the Keychain Access application.
- In the Keychain Access application, select the “login” keychain and click on the “Add” button.
- Enter your password to confirm the installation of the certificate.
3. Disable Digital Signature Verification
If none of the above solutions work, you can disable digital signature verification in your mail application. However, this is not recommended as it can compromise the security of your email communications.
To disable digital signature verification in Mac Mail, follow these steps:
- Open the Mail application and click on the “Mail” menu.
- Click on “Preferences” and then click on the “Accounts” tab.
- Select the account for which you want to disable digital signature verification.
- Click on the “Advanced” tab and then uncheck the box next to “Verify digital signatures”.
- Click on “Close” to save the changes.
It is important to note that disabling digital signature verification can make your email communications less secure. Digital signatures help ensure that the contents of your email have not been tampered with during transmission and that the sender of the message is authentic. If you disable digital signature verification, you will not be able to verify these important aspects of your email communications.
Conclusion
The “Unable to verify message signature” error in Mac Mail can be frustrating, but there are several steps you can take to resolve the issue. Checking the digital certificate, updating your mail application, adding the certificate to your Keychain, and disabling digital signature verification are all possible solutions. However, it is important to note that disabling digital signature verification can compromise the security of your email communications. If you are unable to resolve the issue on your own, it may be necessary to contact your email service provider for assistance.