After installing Rollup 1 for Exchange 2007 SP3 IMAP is now serving most text/plain parts as text/html instead. I had some issue with a simple mail import tool that now imported all mail with html codes.
Before the rollup 1 they were previously multipart/alternative messages with both text/plain and text/html subparts.
Solution:
You can set in through in the GUI or using Powershell to set the value to 0 text only
ImapMessagesRetrievalMimeFormat:
0:Text Only
1:HTML Only
2:HTML and Alternative Text
3:Enriched Text Only
4:Enriched Text and Alternative Text
5:Best Body Format
Exchange Management Console:
-
In the console tree, expand Server Configuration, and then click Client Access.
-
In the work pane, click the POP3 and IMAP4 tab.
-
In the work pane, select IMAP4 and then, in the result pane, click Properties.
-
On the IMAP4 Properties page, click the Retrieval Settings tab.
-
In the Message Retrieval pane, select a message format from the drop-down list under Message MIME format. I choies for 0
-
Click Apply, and then click OK to save your changes.
Powershell:
Set-CASMailbox -Identity yourcasserverhere -PopMessagesRetrievalMimeFormat 0
