Assume that you are using Microsoft BizTalk Server. When an XML message is sent to Multi-purpose Internet Mail Extensions (MIME) encoder, the byte order mark (BOM) isn't removed by the MIME encoder if Content-Transfer-Encoding is 8-bit. In this situation, you may receive the following message, in which BOM characters aren't removed:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For information about the service packs and cumulative update list for BizTalk Server, click the following article number to view the article in the Microsoft Knowledge Base:
2555976 Service pack and cumulative update list for BizTalk Server
For more information about BizTalk Server hotfixes, click the following article number to view the article in the Microsoft Knowledge Base:
2003907 Information about BizTalk hotfixes and Service Pack support