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Home » GFI User Forums » Kerio Connect » Malformed MIME content causing all mail to be rejected
Malformed MIME content causing all mail to be rejected [message #119508] Wed, 18 February 2015 18:29 Go to next message
gbrown100 is currently offline  gbrown100
Messages: 34
Registered: April 2008
Location: Sussex, UK
I have a client using Connect 8.4.1 (3789), their biggest client (global company) is rejecting all their email, they have given me the following reason. Any ideas?

Thanks, Graham

If a Message Processing Failure returns a 'Bad-data' response with the following description 'The Content-Type Header is Invalid', the gateway cannot recognise the message header.
Refer to and see section 5.1 - Syntax of the Content-Type Header Field for further information.

In the Augmented BNF notation of RFC 822, a Content-Type header field value is defined as follows:

content := "Content-Type" ":" type "/" subtype
*(";" parameter)
; Matching of media type and subtype
; is ALWAYS case-insensitive.

type := discrete-type / composite-type

discrete-type := "text" / "image" / "audio" / "video" /
"application" / extension-token

composite-type := "message" / "multipart" / extension-token

In this case, the original mailer has not composed the mail correctly as they have missed out the discrete type.
Currently the message is not RFC compliant.

It is recommended that the sending host of the message should be contacted and informed of this error so they can resolve the malformed mime content.

[Updated on: Wed, 18 February 2015 18:30]

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Re: Malformed MIME content causing all mail to be rejected [message #119511 is a reply to message #119508] Wed, 18 February 2015 18:47 Go to previous messageGo to next message
Kerio/GFI Brian is currently offline  Kerio/GFI Brian
Messages: 852
Registered: March 2004
Location: California
It seems that the receiving mail server has an issue with the formatting of the message. What mail client are you using to compose the message? Does this happen if you use Kerio Connect Client or Webmail? Have you configured a domain footer or special type of email signature?

Brian Carmichael
Instructional Content Architect
Re: Malformed MIME content causing all mail to be rejected [message #119523 is a reply to message #119511] Thu, 19 February 2015 10:54 Go to previous message
Messages: 356
Registered: April 2005
we need example of such message (.eml source)
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