You will need to make sure this is configured on your Windows Server for distribution file to be downloaded to the devices correctly.
Setting server MIME types
You may need to configure your web server so that the manifest file and app file are transmitted correctly.
For Mac OS X Server, use Server Admin to add the following MIME types to the MIME Types settings:
application/octet-stream ipa
text/xml plist
For IIS, use IIS Manager to add the MIME type in the Properties page of the server:
.ipa application/octet-stream
.plist text/xml
Article ID: 97, Created On: 11/14/2013, Modified: 11/15/2013