Multiple redirect/respond invocations not allowed

Since the rule will always evaluate each conditional, a single request could result in multiple HTTP::redirect statements. For example, a request for http://www.abc.com/ would match both the TCP::local_port != 443 and the HTTP::uri == "/" conditions. This rule will not encounter this problem:

when HTTP_REQUEST {
   if {[TCP::local_port] != "443"} {
      HTTP::redirect https://[HTTP::host]/exchange
   } else {
      set my_uri [string tolower [HTTP::uri]]
      if { $my_uri starts_with "/exchange/customerservice" } {
         HTTP::redirect https://[HTTP::host]/exchange
      } elseif { $my_uri eq "/" } {
         HTTP::redirect https://[HTTP::host][HTTP::uri]/exchange
      }
   }
}

Of course, I am making some assumptions about exactly what behavior you are looking for, but you should be able to rearrange this framework to achieve whatever logic you need.