Anthony,

> This particular site is running Win XP Home SP1. I have a
> reasonable amount of freedom for testing over the next day or
> two. Once again, I
> am sure I have run into this situation due to some changes in my
> code,
> but I can't identify that change right now.
>

> Does anyone have any thoughts on why an IB_Event would stop
> firing (when Registered = true)?
>

Is it the server who stops sending the events or is it the client who stops
properly receiving/handling them.
You could write a simple program which only receives the events and logs
them into a textfile, just to further narrow down the problem.
I take it that you are aware of the problem some of us had with W2K SP4.
Apparenty MS changed something on their TCP handling so that events didn't
reach the clients anymore. A QaD fix was to use the TCPIP.SYS of SP3
instead.

Florian