Server's response could not be processed. Content-Length header is invalid. This could be caused by a malformed response, or possibly a misconfiguration.
The reason why ProxySG has response invalid response is because the Server or Web site has added a ";" after the content-length field which is not a supported by RFC standard and only numeric values are allowed in the Content-Length header value. There is no workaround in the ProxySG. The only workarounds at this time either bypass the proxy for access to the site or contact the OCS admins or webmaster to resolve the issue on the site itself.
The customer can reach out to his or her SE and file/submit a feature enhancement request to have this exception added to the policy (to ignore any field after the content-length header).