GMail says 451 4.5.0 SMTP protocol violation, see RFC 2821. What the hell does that mean? ~ Ask The Admin

Thursday, July 17, 2008

GMail says 451 4.5.0 SMTP protocol violation, see RFC 2821. What the hell does that mean?

My mailserver pretty much told me to go fluck myself this morning when I was trying to send out some email. It looked like emails to any gMail account was returning the following error message:

Delivery failed 5 attempts:

Body of message generated response:
451 4.5.0 SMTP protocol violation, see RFC 2821 23si6651713hsd.10

I went and checked out RFC 2821 like a good admin and checked each of the points. I had a abuse account, a postmaster account... But I was not an open relay to begin with. WTF?

This happened shortly after an upgrade from iMail 2006 to iMail 10.01 (2008). I checked my settings and then rechecked my settings. I had enough and called into IPSwitch Support. Strangely I got one of the lead developers on the phone who worked with me. After a few hours of him poking around my production mail server he kinda shrugged his shoulders and gave me a

"Man I have no idea."

Not so reassuring...

Not at all. I started sending test messages to other accounts on the web and I was not seeing any issues. Again I said

WTF? Why is Google hating on me?

Then I noticed it. There was a footer at the bottom of my email that was in my account, and I had eliminated that footer almost 3 years ago. I asked the tech support dude about it and he said it would live in a file called trailer.txt in the iMail root folder. I deleted it and WHAMO!

Gmail was listening to me again.

A very grueling few hours with loads of people making up excuses on how they need to email people on gMail for work... YEAH RIGHT! Did you think I wasn't working on it?

Don't you have some TPS reports that need to be filed on those new cover sheets?