Some incoming emails being rejected on new email-enabled list

Question

I've just set up a new SP list to log purchases made by our department. Whenever we buy something, we'll use the email address corresponding to a distribution group that contains myself and an Exchange contact for a list in SharePoint.

I've set the list to receive mail from any sender and preserve attachments. It's a Discussion list, because I want to keep both the contents and attachments. I tested it from Gmail and it worked as expected.

Now we've purchased some software. This purchase triggered five emails. The SharePoint list only received two of them. Looking in the logs, I have:

The file you are attempting to save or retrieve has been blocked from this Web site by the server administrators.<nativehr>0x800401e6</nativehr><nativestack></nativestack>

An error occurred while processing the incoming e-mail file C:\inetpub\mailroot\Drop\c49c754f01cd766d00000108.eml. The error was: The file you are attempting to save or retrieve has been blocked from this Web site by the server administrators..

To my knowledge, we've never had this issue before with email-enabled lists and we use them rather heavily. Two of the three messages blocked had no file attachments at all and were sent plaintext. All five came from the same source address. If the logs at least told me what file or filetype was being blocked, that might give me somewhere to start, but since it doesn't, and since SharePoint cheerfully tosses the .eml after processing, I don't really have much to go on.

The text of one of the email messages is as follows:

x-sender: [email protected]
x-receiver: [email protected]
Received: from exchange.mydomain.com ([10.0.0.52]) by sharepoint.mycompany.com with Microsoft SMTPSVC(7.5.7601.17514);
     Fri, 10 Aug 2012 08:44:18 -0400
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.3790.4721
Importance: normal
Priority: normal
Content-class: urn:content-classes:message
MIME-Version: 1.0
Content-Type: text/plain;
    charset="utf-8"
Content-Transfer-Encoding: base64
Subject: Payment Receipt from Some Vendor
Date: Fri, 10 Aug 2012 08:44:20 -0400
Message-ID: <[email protected]>
X-MS-Has-Attach: 
X-MS-TNEF-Correlator: 
Thread-Topic: Payment Receipt from Some Vendor
Thread-Index: Ac12bhVqmh8qr8JLTkKi80TzqzDBzwAh7wew
From: "Drew Lanclos" <[email protected]>
To: "IT Purchasing" <[email protected]>
Return-Path: [email protected]
X-OriginalArrivalTime: 10 Aug 2012 12:44:18.0437 (UTC) FILETIME=[DB722B50:01CD76F5]

KiogUGxlYXNlIGRvIG5vdCByZXBseSB0byB0aGlzIG5vdGlmaWNhdGlvbi4gVGhpcyBtYWlsYm94
---snip---
LS0NClRoZSBBdmFuZ2F0ZSBUZWFtDQpBdmFuZ2F0ZSBJbmMNCmh0dHA6Ly93d3cuYXZhbmdhdGUu
Y29tDQpzdXBwb3J0QGF2YW5nYXRlLmNvbQ0KDQpbW2xjdks1SlhjZ0g0PV1dDQoNCg==

Answer 1

I read in this thread that Sharepoint will only pick up messages that have x-sender and x-receiver headers. We use hMailServer, and so are able to script the server to add those headers for Sharepoint-destined messages.

Here is another possibility, from here:

For SharePoint 2010

Delivery of e-mail messages is not enabled from SharePoint to other lists within WSS sites. SharePoint filters out e-mail messages when an e-mail message has a destination address of an e-mail-enabled list.

SharePoint checks for the following field in the EML:

X-Mailer: Microsoft SharePoint Foundation 2010

If this field has that value, SharePoint filters that e-mail and does not enable delivery of that e-mail to the list.

Resolution: E-mail messages to SharePoint e-mail enabled lists or document libraries must originate from non-SharePoint senders.

A workaround would be to send the email to another email server and back into Sharepoint - OR edit the mail headers. There is another workaround-solution here.

Yet another thing to look for, having considered your server response, is whether the mime-types are allowed/enabled on your servers iis. If you lack the mime-type (file type; i.e., extension), the server won't let you do anything at all with the files.