Cannot autopost to Stumbleupon. Using Version 3.8.7

Array ( [pgID] => [isPosted] => 0 [pDate] => 2017-09-06 18:12:46 [Error] => Something went wrong – Connection ERROR 3: Array ( [headers] => Array ( [server] => Apache [p3p] => policyref=”/w3c/p3p.xml”, CP=”CURa ADMa DEVa PSAo PSDo OUR BUS UNI PUR INT DEM STA PRE COM NAV OTC NOI DSP COR” [access-control-allow-origin] => https://www.stumbleupon.com [access-control-allow-headers] => Accept, Content-Type, X-Su-ConsumerKey, X-Su-AccessTokenKey, X-Su-ClientId, X-Su-Version, X-Requested-With, X-Token, X-API-Version, X-Su-Branch, X-Su-Hash [access-control-allow-methods] => DELETE, GET, POST, PUT, OPTIONS [access-control-max-age] => 86400 [access-control-allow-credentials] => true [vary] => Accept-Encoding [content-encoding] => gzip [content-type] => text/html; charset=utf-8 [content-length] => 125 [accept-ranges] => bytes [date] => Wed, 06 Sep 2017 18:12:47 GMT [age] => 0 [connection] => keep-alive ) [body] => {“_timestamp”:1504721567,”_sub_errors”:[],”_success”:false,”_error”:”Client version not specified”,”_reason”:[],”_code”:815} [response] => Array ( [code] => 500 [message] => Internal Server Error ) [cookies] => Array ( ) ) )