SMTP Err: 554 One or more recipients failed.

How big is the attachment? Mail servers can have limits on the size of the email. Are you on the bellsouth network?

I know that this is not an size issue because all of my emails are blocked, no matter the size. I allowed another tech to diagnose this issue. He said that bellsouth's mail server may be blocking my mail as if it were spam. I am sending email from my multi-function printer that has email capabilities on the bellsouth network. The emails sent from the printer are being blocked. If they are being labeled as spam, I will scan the file to my PC and email it from there as an attachment.

Is the email going directly from the printer to the bellsouth network? If so then I understand why it is being blocked – it is probably not behaving like a totally proper SMTP client, instead taking some shortcuts with the protocol. The bellsouth email servers are probably configured to require high compliance with the spec to reduce spam, as spam clients also tend to take shortcuts. If you had your own SMTP server to relay through first then it would probably work.

Yeah, I believe that would work. Thanks for the info. We may look into getting our own mail server so that we can monitor the settings ourselves. In the meantime, we decided to just scan our documents to a folder on our hard drives and attach them to emails if needed. This is a feasible work-around until we get our mail server configured to our liking. :D