Why do I get a 400 – bad request error using the following URL? It is encoded using Server.UrlEncode. The actual path query parameter is C:\Development\Chase\Exports\ChaseExport-090312073930.zip
http://localhost:50199/Common/Forms/Export_Stream.aspx%3fpath%3dC%3a%5CDevelopment%5CChase%5CExports%5CChaseExport-090312073930.zip
You should not urlencode the entire querystring, just the values, so URL should be