Examined a server recently that refused to download deployed security updates. This server was also a Distribution Point in a remote location. Further, this site is running CM Current Branch.
Software Center presented the following:
DataTransfer.log showed something similar to the following:
Successfully sent location services HTTP failure message. Error sending DAV request. HTTP code 500, status 'Internal Server Error' GetDirectoryList_HTTP('http://<server>:80/SMS_DP_SMSPKG$/<guid>') failed with code 0x87d0027e. DataTransferService 4/29/2016 8:51:36 PM 3028 (0x0BD4) Error retrieving manifest (0x87d0027e).
After review, content boundaries were correct, DP was installed correctly. Enabling HTTP anonymous authentication did not help.
Found a similar problem on the web, with a tip to enable ASP.NET 4.5:
Adding the ASP.NET 4.5 Role (and proposed Features) under Roles and Features > "Web Server (IIS)" > "Web Server" > "Application Development" solved our issue.
For more details see http://go.microsoft.com/fwlink/?LinkID=216771
Took these steps, rebooted the server and all is well.