Why I hate Exchange

Posted by nuxi on 2009-Nov-12 at 17:35:02 in Computers (Login to reply)

I have a bit of a problem with an MS Exchange server some of my mail is controlled by. The biggest issue is that Exchange is munging the mail contents.

Exchange supports two different mail protocols. (well, 3, but we are going to ignore X.400) The first one is what you might call the native Exchange storage format and protocol, MAPI. MAPI is also the protocol used by MS Outlook to talk to Exchange.

The second protocol is the standard SMTP format message called RFC822, or sometimes called MIME format in the Exchange documentation. This is the format used by SMTP, POP3, and IMAP. This is the format used by Exchange when it needs to talk to the real world.

Exchange 2003 stored messages in two different databases. One database stored mailed that arrived in MAPI format, the other stored mail that arrived in RFC822 format. Mail would be converted on the fly from one format to the other as needed.

Now this conversion from one format to the other causes some loss of information, such a thing is inevitable. So obviously, its important to only do this conversion when necessary right?

Exchange 2007 only stores mail in MAPI format. All incoming mail is converted to MAPI and it is converted back to RFC822 format if needed. So if you are an IMAP client to Exchange 2007, your mail is converted from RFC822 to MAPI and then back to RFC822.

Yeah, that double conversion works about as well as you might expect.