Remote Assistance Error

I am reposting this because I fear that nobody saw my
other post at midnight a few days ago. I desperately need
advice in this matter.

I assist others by remote assistance several times a day
on many other systems running XP Pro like myself. Most of
us are running MSN Messenger 6.x as a chat interface, but
I realize the core of the problem I am about to discuss
is related to Windows Messenger 4.7 (latest version). I
have been doing this successfully for ages and realize
the difference between a normal failure and what I am
about to discuss.

Background. The newly configured system I am trying to
connect to (Intel 865PE chipset with on-board LAN) was
installed on a home network (Netgear 4-port router), and
was mistakenly connected to the computer from a RJ-45
cable into a RJ-45/USB adapter, and then a USB connection
into the computer. I was not aware of the RJ-45/USB
adapter unnecessarily being in the loop. We had a normal
remote assistance session at that point.

I was troubleshooting hooking up one of her USB 1.1
Printers and noticed in the Device Manager that she had
somehow managed to knock out her USB 2.0 device. The
system has all the latest XP updates and should have no
trouble detecting the USB 2.0 device. Naturally, I
removed the recalcitrant device to reinstall it properly,
and without knowing about the unusual network hook-up, I
was immediately disconnected from the remote system.

The immediate attempts to reconnect to a Remote
Assistance connection resulted in the following message
right before the "Take Control" option is supposed to
become available: "has closed connection to your
computer." There was no subject like "[Username] has
closed connection to your computer." On the top of the
Remote window, there was a message saying Disconnected
from [Username].

After we discovered the USB network connection, I had her
hook up the RJ-45 connector cable straight from the
router to the computer, eliminating the RJ-45/USB
adapter. We completely powered down everything including
router and cable modem for several minutes and brought
the system back on line through standard procedures.

The same Remote Assistance error continues time after
time even after removing the USB Network connection.
There is no USB type device in Network Connections. All
of the USB 1.1 and 2.0 devices are working properly now.
Why can I NOT connect to this computer? I can connect to
another computer before attempting hers and afterwards.

This is very bizarre. I must assume it has something to
do with the way I removed that USB Device in Device
Manager mentioned above while connected via that method.
The closest thing to this in the Microsoft Knowledge Base
is Article 300067, and both NT Authority Authenticated
Users and Interactive groups are present. The article
does not say how to remove them so that I can add them
back again. Could this approach make a difference? I'm
also thinking of temporarily removing ALL USB devices in
Device Manager to see if we can connect after that. I
can't go to the remote site to do this myself to perform
this however. Any advice would be appreciated. I need to
do remote tutoring on this machine. Sorry for the book
here. Thank you.