We have ARR configured to load balance 5 sites with two web servers behind the ARR server. 4 of the sites are static sites with one of them serving dynamic data with SQL server access. We had not patched for quite a long time and did so last week. Since then the site that serves dynamic data is erroring most times it performs a post back. Not all times, but most. When it does it gives the error: 502 Web server received an invalid response while acting as a gateway or proxy. When the webserver (acting as gateway or proxy) contacted the upstream content server, it received an invalid response from the content server.
Thanks for any help!