Email

Fix the ‘Email server certificate is invalid’ error

Definitions

An invalid email server certificate error means you can’t verify the email server’s identity, which may cause security warnings or connection issues on the email application on your device.

Depending on your device and email application, the email server certificate is invalid error can appear in different formats, such as:

  • Cannot verify server identity.
  • Server certificate is not trusted.
  • Security certificate error.
  • Connection is not secure due to invalid certificate.
  • Server identity cannot be verified.
  • Email server certificate error.

Here is a visual example of the ‘Email server certificate is invalid’ error:

Before you start

✅ The ‘Email server certificate is invalid’ error can be fixed easily and quickly.

ℹ️ Follow each step by step fix below in order, moving to the next only if the previous one doesn’t work.

Step by step

Check your IMAP and SMTP settings

Sometimes, incorrect IMAP and SMTP settings in your email application can trigger the email server certificate is invalid error.

1. Open this guide: Use IMAP and SMTP to connect your email to email apps

2. In that guide, find the IMAP settings section and double check the IMAP settings in your email application match

3. In that guide, find the SMTP settings section and double check the SMTP settings in your email application match

4. Once you’ve reviewed all your settings, see if the error has cleared

Check your SSL certificate

1. Open this guide: Install an SSL certificate and enforce HTTPS on your domain

2. In that guide, review all the steps to make sure your SSL certificate is active, or manually install it to activate it on your email domain

3. Once you’ve verified and/or activated your SSL certificate, see if the error has cleared

Bypass the error

Depending on your device and email application, this error may be falsely triggered, meaning the certificate is valid but not read properly. Simply press ‘Accept’, ‘Close’, or ‘Okay’ on the warning to bypass it.

Your email will work fine, and the error will clear on its own.