See here:
Why can't I join a homegroup?
http://windows.microsoft.com/en-us/windows7/Why-can-t-I-join-a-homegroup
Esp.:"The network location might not be set to Home. HomeGroup only
works on home (private) networks. To change your network location,
follow these steps:"
I have also found that WIn7 networks seem to work better with passwords
installed.

This recent Windows Secrets article may be of help after you've
connected:

Simple change in settings pumps up Win7 networks:
http://windowssecrets.com/2010/10/14/01-Simple-change-in-settings-pumps-up-Win7-networks



-------- Original Message --------
Subject: Re: [PCBUILD] Laptop not working on Win 7 homegroup
From: Tom Waddell <[log in to unmask]>
Date: Fri, November 05, 2010 11:17 am
To: [log in to unmask]

thanks. laptop running win 7. only win 7 firewall. just setup both
desktops with win 7 and a homegroup. no problem. mapped network on
laptop. all 3 computers show up. all computers get to internet through
same cisco router. desktops are wired, laptop is wireless

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