A simple chat site. onDisconnect the userlist (sharedObject) gets revised and a
message is posted that a user has left the room. Sometimes there are users who
have left and have not been removed. This does not happen all the time. Any
ideas/help would be more than welcome.

The macromedia support really sucks for FlashComm technology isnt it ?

Well , this is how i do it :

i do a setInterval() function on the server side and set it to call a function
that loops through your clients and gives them ping. like :

applicaiton.intervalFunc = function()
{
for( i=0;i<application.clients.length;i++)

if(!application.clients.ping())application.rejectConnection(application.clients)
;
}

this way you will force their disconnection if they dont respond to ping (
they lost connection without calling onDisconnect )

There is also a bug that does this, install updater 2 and you will have on
cause down.