We recently had an issue where a user was replying\forwarding an email from an external user. The email had the smart banner on it from the external user. When our user replied to the email our internal users that received it saw either a blank email or a very large yellow box, like the smart banner blew-up in size. This has happened the last 2 times this user either replied to or forwarded an email with a banner attached. A screenshot below shows the blown-up yellow banner.
If we manually remove the banner info before forwarding the email, it all send fine. Has anyone encountered this before?
Thank you for contacting the Sophos Community.
I would recommend you to open a case with Support to get this investigated, however when opening the case, please add if you’re using ToC and what email client is being used, and server (e.g Exchange, O365), and provide the chain of emails, (originals) so it can be investigated.
Would be interesting to see what causes it. I've seen similar things with signatures and various email clients where the image just goes mental large. Almost as if something isn't complying with standards.
Can you replicate it with another user or webmail client?
If you do find out what causes it please let us know.