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We've seen a few reports now where SBS 2003 Alert Emails are not being received. In addition, you may be receiving NDR's from your ISP complaining about "bare line feeds" in the message.
If you think back to your Programming 101 days, there's always a chapter that covers the mystical inner workings of the CString. You learn that, when you hit the Enter key at the end of a sentence in a DOS or Windows application, you are really inputting two characters - a carriage return (the typewriter carriage moving all the way back to the left) and a line feed (the paper scrolling forward).
There are many text editors and OS's that use the linefeed character as the delimiter for a new line. And, in the code that generates the email alerts in SBS, that is what we use. However, for SMTP mail, a new line should technically be rejected, based on RFC 8222:
RFC 2822:2.3. BodyThe body of a message is simply lines of US-ASCII characters. Theonly two limitations on the body are as follows:- CR and LF MUST only occur together as CRLF; they MUST NOT appearindependently in the body.- Lines of characters in the body MUST be limited to 998 characters,and SHOULD be limited to 78 characters, excluding the CRLF.Note: As was stated earlier, there are other standards documents,specifically the MIME documents [RFC2045, RFC2046, RFC2048, RFC2049]that extend this standard to allow for different sorts of messagebodies. Again, these mechanisms are beyond the scope of thisdocument.
You can see this quite clearly in a Network Monitor (NetMon) capture:
In practical terms, IE, Outlook, Word, and just about anything else people typically use to read or render mail renders the bare line feed as a CRLF. You get the message, it displays, no one is any the wiser, we all go home happy. The trouble comes in when a remote email server is configured to reject mail with bare line feeds.
This is the workaround we've used and are suggesting our customers use when you need to send email alerts from SBS to an account using a mail server that rejects the bare line feeds:
To workaround this issue you will configure Outlook to redirect the email which results in the message being reprocessed and the bare line feeds removed. To do this:
We would like to Thank Mr. Azzara for bringing this issue to our attention and helping test the workaround.
Sometimes antivirus can be the "cause" of problems and not the prevention of them.... case in point...
[Today's post comes to us courtesy of Shawn Sullivan] “Unable to send email to certain domains” is a
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