Hello BillWalsh1,
The message that you are trying to send is too large or exceeds your recipient's mailbox limit. This usually happens when the host of your recipient has a limit on the size of messages that they can receive. Reduce the size of your message. If you are trying to send a file, you may need to compress it using a file compression program, like WinZip.
However, you've mentioned that the attachment is not that large. For us to gain a better grasp of your concern, we need to gather the following information:
- Is this the first time you've encountered this issue?
- Are you using a browser or the Mail app to access this account?
- Are you also experiencing the same when forwarding the same email using other email accounts?
It also seems that you're forwarding it to a lot of recipients, I advise to send it to just one recipient and check if the error occurs.
To notify us and have us get back to you, simply reply to this post.