SharePoint Designer 2013 error : server could not complete your request [FIX]

I was facing this issue while connecting to my SharePoint2013 farm from SharePoint Designer 2013 . It was throwing this error:

“The server could not complete your request”

I had to kill the SPDESIGN.exe process forcefully.

Solution:

I got rid of this error by to enabling anonymous authentication  on “SharePoint Web Services” web Application . I found the solution here.