- You have a downstream proxy that has Microsoft Forefront Threat Management Gateway (TMG) 2010 installed.
- You configure network traffic interoperability between the downstream proxy and an upstream proxy.
- A client computer tries to create a Secure Hypertext Transfer Protocol (HTTPS) connection through the downstream and upstream proxies to a web server.
- HTTP/1.1 502 Proxy Error (Arithmetic result exceeded 32 bits.)
- HTTP/1.1 502 Proxy Error (-2147471495) ERROR_HTTP_INVALID_HEADER
When you try to create a HTTPS connection, the downstream proxy that has Forefront TMG 2010 installed forwards the HTTPS CONNECT request to the upstream proxy. The upstream proxy returns a response packet that has some additional headers. However, Forefront TMG 2010 cannot parse the response if the returned packet is split into multiple packets.