I just had an interesting problem when accessing a HTTPS (SSL) service in Firefox. I got the following error message.
SSL received a record that exceeded the maximum permissible length. (Error code: ssl_error_rx_record_too_long)
It turned out the the HTTPS service (on port 443) was not actually a HTTPS service and it was configured as a normal HTTP service. The initial connection from the browser was communicating in HTTPS, and expecting a security certificate, but instead it was getting back the normal HTTP “Bad Request” HTML. A confusing error message, but an easy problem to fix.