KB Article #177172

Websockets do not work on ports where gzip or deflate compression has been enabled

Problem

* Websocket connections do not work properly on ports where 'gzip' or 'deflate' compression is enabled on the Advanced tab, under input & output encoding.

Resolution

-- Compression should not be enabled on any port with websockets. Websockets use their own binary protocol and none of the major browsers understand websocket frames that have been compressed in this way.