Webmail Fails to Load Contacts or Send Emails when a Signature Image or Session Token is broken

Symptoms

When sending an email from a specific account, the image in the reply body is broken, and a connection error occurs. You may see errors such as:

• 401 Unauthorized errors when opening or replying to emails
• Webmail fails to load contact lists
• Broken images in email replies

Cause

The issue concerns an image embedded in the user's email signature. Images that include session-based URLs can cause errors such as broken images, 401 errors, or the contact list failing to load.

Resolution

1. Log in to your webmail account.
2. Click on Settings.
3. Click on Identities.
4. Select the affected identity.
5. Edit the Signature.
6. Remove any images that are linked via session-based URLs.
7. Select the HTML button in the top left, under Signature.
8. Select the Image Icon, then re-upload the image using the Webmail image upload tool to insert it.
9. Save the updated signature.

Additional Resources

cPanel Docs | How to Set Up a Signature in Webmail

How to add a Signature in Roundcube