Have you checked this link?
Vista Slow IssuesThe following links may help. Vista: very slow to copy large files ... Vista Slow issues ... of Vista) it is very slow to resolve folder names. ...
http://www.chicagotech.net/vista/vistaslow.htm
Bob Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on
http://www.ChicagoTech.net
How to Setup Windows, Network, VPN & Remote Access on
http://www.HowToNetworking.com
"Duo64" <Duo64.2q2td6@no-mx.forums.net> wrote in message news

uo64.2q2td6@no-mx.forums.net...
Hi,
I realize that there are already a ton of threads on Vista/XP file
sharing problems but I have did a search and non of them addresses my
specific problem, nor does it contain the same case that I have.
My setup consists of a new HP laptop dv6375us with vista home premium
and a desktop running xp pro. Both computers are connected to a D-Link
wireless router, with the desktop always on wired LAN and the laptop
with either LAN or wireless.
Now heres the problem, transfer speeds on wireless seem to go ok, with
speeds up to 1megabyte/sec, going either way. But on wired LAN, i get
really slow speeds of up to only about 200kbyte/sec max, with tons of
fluctuation. I have tried disabling the norton security that comes with
the laptop, playing with the firewall rules....windows firewall always
disabled....everything....nothing seems to fix this problem. I've tried
disabling ipv6 as well as the compression method that everybody seems to
be talking about.
any type of help on this matter, or anybody with a similar problem who
knows how to solve this would be greatly appreciated. Thanks.
--
Duo64