Enable HTTP PUT for .net 3.5 application in IIS 7.5. Getting error IIS 7.5 Detailed Error - 405.0 - Method Not Allowed

I am facing an issue while posting http using request type PUT, it is not enabled on IIS, can someone help me on how to enable PUT request type via web.config changes. My another post regarding on stackoverflow ishttp://stackoverflow.com/questions/33215702/enable-put-for-net-3-5-application

Basically i have a ashx handler which is currently accepting only GET and Post request. Now some external application send information in http PUT type but my application is throwing

IIS 7.5 Detailed Error - 405.0 - Method Not Allowed

Failed Request Tracing logs:

<failedRequest url="http://localhost:80/.../TestHandler.ashx"
               siteId="1"
               appPoolId="DefaultAppPool"
               processId="10708"
               verb="PUT"
               remoteUserName=""
               userName=""
               tokenUserName="NT AUTHORITY\IUSR"
               authenticationType="anonymous"
               activityId="{00000000-0000-0000-3D85-0580000000FE}"
               failureReason="STATUS_CODE"
               statusCode="405"
               triggerStatusCode="405"
               timeTaken="0"
               xmlns:freb="http://schemas.microsoft.com/win/2006/06/iis/freb">