It sounds like “something” is different about the laptop with the delay. One
thing you might want to try is to actually look at the packet traffic from
that machine. There are several free software packages you could use and
WildPackets has made OmniPeek Personal free. You can get that here:
http://www.omnipeek.com/. What you want to look at is what the packet
traffic looks like without any network software loaded, i.e. Internet
Explore, IM software, Groove, etc... You may have a virus, worm, or rootkit
running on that machine which can cause this type of slow down.
Once you’ve made sure that nothing is going out or in that you don’t expect,
you could try moving the laptop to another network connection that you know
works fine. This would be a quick way to eliminate possible problems with
your network hardware.
Other than that, I would look at the GAC, maybe you need to clean that up a
little. Maybe play around with a dependency walker to make sure that
dependencies are where you expect them to be.
Good luck,

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