To add to this...I run into this quite a bit with admin's who have no idea what they are doing or how to configure their systems, but they can quote gibberish really good.  Good enough to fool their bosses into thinking they know what they are doing.... A good admin can tell you EXACTLY why a message is being blocked or sent to some kind of spam folder and can fix the problem if wrong.

I am being denied delivery of emails sent through another's Symantec Brightmail Gateway.

I was told that Pegasus emails cannot be scanned by the gateway, because

"[the emails with] malformed MIME types are flagged with
this verdict ("malformed_mime") because the email does not strictly conform to the
RFCstandards in RFC 822 and 2822. The Brightmail Gateway is very strict
inadherence to RFC standards for the MIME header information."

Even emails with no attachments are being flagged "malformed_mime". 

What can be done to solve/work-around this?

Any help would be greatly appreciated.
--Tim

Pegasus Mail has been MIME-compliant since the earliest versions of MIME came out, which is nearly fifteen years, probably anything up to three times as long as Brightmail has been around. Now, MIME is a complex specification, and it's possible that there is *something* in there that I'm not doing correctly, but there is certainly *nothing* in there that prevents normal interoperation with practically every other MIME-compliant system ever invented.

In order for me to have any chance of doing anything about this, I would need to know exactly what the Brightmail gateway is objecting to. Absent that information, there is quite literally nothing I can do.

If you can extract from Symantec some indication of exactly what they think the problem is, I will certainly look into it: if it turns out that they are correct and there is an error in my implementation, I will fix it. I can't do better than this, sorry.

Cheers!

-- David --

Just another small point about this: whomever you received this diagnosis from clearly has an imperfect understanding of what they are talking about. RFC822 and 2822 cover basic Internet Mail, and have nothing whatsoever to do with MIME, which is covered in RFCs 2045 - 2050, with others extending it later. This should make you treat the pronouncements you're receiving from this person with some skepticism. Make sure you actually deal with someone who really does understand the issues here.

Cheers!

-- David --

The people, that are blocking our "malformed_mime" emails (with no attachments mind you),  told me to use the message lint tool at:

http://tools.ietf.org/tools/msglint/

When I can get msglint to work, Pegasus emails get trivial(?) warnings and errors, but no "MIME error"

Have you used this tool to monitor compliance?

I checked the Symantec Support site. There have been a few dozen problems with false positive unscannable verdicts from malformed_mime.  I'm assuming that a Symantec work-around to my problem is possible.

Thanks for your time.
--Tim

[quote user="timpease"]

The people, that are blocking our "malformed_mime" emails (with no attachments mind you),  told me to use the message lint tool at:

http://tools.ietf.org/tools/msglint/ [/quote]

I haven't been able to find any message which passes that validator - whether originated from Pegasus Mail or other mailers.  It appears to use an unnecessarily strict interpretation of the rfcs which makes a lot of its warnings unhelpful and misleading.

Since you can't see the final form of the message that is being rejected, you need to see the output that they get from the lint tool - it is possible that any corruption that they see has been introduced by a server or device along the route.

[quote]I checked the Symantec Support site. There have been a few dozen problems with false positive unscannable verdicts from malformed_mime.  I'm assuming that a Symantec work-around to my problem is possible.[/quote]

That would seem to be a good tactic to follow if you can't get the original admins to give you more information.