I have a situation where 3 PC's (1 desktop and 2 notebooks) must connect to
the Internet by individual wired LAN connections for IP tracking purposes.
This is governed by a mandate from our leased office management that cannot
be changed. What I want to do is introduce a wireless network so that the
notebooks can connect to the desktop for printer and file sharing purposes
only whilst retaining internet connectivity via the LAN to satisfy office
policy. I am trying to find out if more than one network connection can be
active at the same time (LAN & Wireless) or if there will be conflict or if
there is a smarter way of achieving the same objective. The desktop runs
XPProSP2 and the notebooks are XPProSP2 and XPHomeSP2

We need more detail to help, but the answer is yes, you can have both wired and wireless network accessing the Internet even they are in the different subnets.

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
  I have a situation where 3 PC's (1 desktop and 2 notebooks) must connect to
  the Internet by individual wired LAN connections for IP tracking purposes.
  This is governed by a mandate from our leased office management that cannot
  be changed. What I want to do is introduce a wireless network so that the
  notebooks can connect to the desktop for printer and file sharing purposes
  only whilst retaining internet connectivity via the LAN to satisfy office
  policy. I am trying to find out if more than one network connection can be
  active at the same time (LAN & Wireless) or if there will be conflict or if
  there is a smarter way of achieving the same objective. The desktop runs
  XPProSP2 and the notebooks are XPProSP2 and XPHomeSP2

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