Error in Downloading Report from Local SSRS Server

I am executing this attached code "SampleScript.ps1" to access my SSRS report in my local server and download the report in pdf format in local drive.The error which I am getting is as follows,Exception calling "SetParameters" with "1" argument(s): "The attempt to connect to the report server failed. Checkyour connection information and that the report server is a compatible version."At D:\SalesReport\SampleScript.ps1:61 char:1+ $rv.ServerReport.SetParameters($params)+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : NotSpecified: (:) [], MethodInvocationException + FullyQualifiedErrorId : MissingEndpointExceptionException calling "Render" with "7" argument(s): "The attempt to connect to the report server failed. Check yourconnection information and that the report server is a compatible version."At D:\SalesReport\SampleScript.ps1:79 char:1+ $bytes = $rv.ServerReport.Render("PDF",+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : NotSpecified: (:) [], MethodInvocationException + FullyQualifiedErrorId : MissingEndpointExceptionException calling "Write" with "3" argument(s): "Buffer cannot be null.Parameter name: array"At D:\SalesReport\SampleScript.ps1:92 char:1+ $fileStream.Write($bytes, 0, $bytes.Length)+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : NotSpecified: (:) [], MethodInvocationException + FullyQualifiedErrorId : ArgumentNullExceptionCan any one please help me in this. Following is the version that I am using,Powershell: 4.0SQLServer: 2014Thanks in Advance !