Symptoms
When you send a file through the BizTalk file adapter to a folder that already contains a file that has the same file name, you receive an error message that resembles the following:
A message sent to adapter "FILE" on send port "Send_Port_Name" with URI "path\file_name" is suspended.
Error details: The FILE send adapter cannot open file path\file_name for writing because it is associated with an unsupported device type.Additionally, BizTalk Server deletes the existing file from the Send folder. The Send instance remains in a dehydrated state. After the second retry, BizTalk Server puts the new file into the Send folder, and finishes the instance.
Resolution
Cumulative update information
The fix that resolves this issue is included in Cumulative Update 2 for BizTalk Server 2013 R2.
Status
Microsoft has confirmed that this is a regression caused by BizTalk Server 2013 R2 CU1.
References
Learn about service pack and cumulative update list for BizTalk Server. Learn about BizTalk Server hotfixes and cumulative update support.