Unable to access PC over Home Network.

Hi,
Suddenly, I am unable to connect to a single PC on my home network. The PC shows up when I click on Network, but attempts to access it yield "Window cannot access
\\RACHELS-PC. Check the spelling of the name. Otherwise, there might be a problem with your network." I am also unable to ping the PC from my ethernet atached PC. Booting the remote PC allows access at first, but it then fails. Both PC's are running Vista. I am able to gain access to two other PC's on the same home network, both of which are running Windows 7.
Thanks in advance,
s660117.

Try \\RACHELS-PC\c$ [or whatever the drive letter is].

Thanks for your reply, townsbg, but I get the same response when I try to manually map to the drive .
A couple of things which I forgot to mention --
My home network consists of my PC, which is ethernet attached and three laptops, two of which run Windows 7, and one - the PC in question, which runs Vista.
All of the devices can connect to one another, with the exception of the Vista laptop: in that case, none of the other 3 PC's can connect.
I am unable to ping the isolated PC from any of the other three: all requests either time out or I am told that the destination host is unreachable.
Ipconfig on the affected device shows --
Windows IP Configuration

Wireless LAN adapter Wireless Network Connection:
Connection-specific DNS Suffix . :
Link-local IPv6 Address . . . . . : fe80::6c1a:3df0:1467:d172%12
IPv4 Address. . . . . . . . . . . : 192.168.1.13
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1
Ethernet adapter Local Area Connection:
Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Tunnel adapter Local Area Connection* 6:
Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Tunnel adapter Local Area Connection* 7:
Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Tunnel adapter Local Area Connection* 11:
Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :

Thanks,
s660117

Is this network all wired/wireless/mixed ??

Hi, Miles,
All three of the laptops are wireless, including the one that is unreachable.
One other thing -- The laptop that I can't access from any of the other PC's is able to connect to the Internet.
s660117

One other thing --
The wireless laptop that we can't access is itself able to access all other PC's on the home network.
s660117

I've always avoided wireless. So I'm not likely to be much help. Have you checked the services on the recalcitrant Vista machine? Maybe it's not running some NetBios name broadcast or something like that. System info tools like LookInMyPC can generate a report in a nice Table format. I would compare the services of one of the working PCs to the Vista machine. See if something got turned off by accident or through some registry corruption. It might not be telling the network its name.

Actually, the problem was more widespread than I reported: it was not local to a single PC, but affected all devices on the local network.
It was, as it turns out, caused by default settings in the firewall implemented by Kaspersky Internet Security, which I had just installed. The default setting for the firewall was public; once it was changed to trusted instead, everything worked as it should and all devices were able to access each other.
s660117

Thanks for sharing. Hopefully this will help someone else.