BizTalk Server accepts timestamps only in the YYYYMMddHHmmss format. When an FTP server responds by using milliseconds as part of the YYYYMMddHHmmss.fff format, you may receive the following error message:
"TimeStamp retrieval failed. Ensure that FTP server supports MDTM command. Server message: “String was not recognized as a valid DateTime.” error and disable the receive location.
This problem was fixed in the following cumulative updates for BizTalk Server:
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 Cumulative Update support