I just went back from a customer that experienced a problem when they used client push to install clients. All client reported the same in ccmsetup.log

Failed to correctly receive a WEBDAV HTTP request.
Failed to successfully complete HTTP request. (StatusCode at WinHttpQueryHeaders: 405)

The solution to this problem is adding this line:
<add name="WebDAV" path="*" verb="PROPFIND,PROPPATCH,MKCOL,PUT,COPY,DELETE,MOVE,LOCK,UNLOCK" modules="WebDAVModule" resourceType="Unspecified" requireAccess="None" />

To the %windir%\System32\inetsrv\config\applicationHost.config file.

  1. Open the applicationHost.config file
  2. Search for the text <handlers accessPolicy="Read, Script">
  3. Add a new line after the text and paste this line: <add name="WebDAV" path="*" verb="PROPFIND,PROPPATCH,MKCOL,PUT,COPY,DELETE,MOVE,LOCK,UNLOCK" modules="WebDAVModule" resourceType="Unspecified" requireAccess="None" />
  4. It should look like the highlighted text in the image.  
    image