Assume that you are using the Microsoft BizTalk Server 2016 SFTP adapter to receive or send files. If the file names contain some special characters, such as '[', the SFTP adapter receive may fail, and it may either not fetch the files or fetch wrong files from the remote location.
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