I reread the entire thread to check facts as well as to pull out what I think is pertinent info, which follows:
1) The two computers were able to communicate via the network previously (so, they should be able to communicate once again).
2) It's an interesting tidbit that your LAN play of SS2 stopped at the same time - did you play it from the XP machine only?
3) Both systems are part of the same named network, being "WORKGROUP".
4) From zeroth's post you were able to identify & rectify the issue with the "restrictanonymous" setting.
5) On the Vista machine the network link in the Network and Sharing Center utility appears to be roaming even when you're actually connected to the "WLAN_AD" network.
6) You're getting error code 0x80070035 on the Vista machine - this can actually be pointing us to the problem now that I've looked up the error code on MS's support pages (
http://support.microsoft.com/kb/958285/en-us). Did you setup a VPN for the two machines which has now failed?
7) You've tried setting up a stand alone network (ie, through the router) with the two machines, temporarily turning off all security programs *after* the network had been isolated, without resolution.
8) It appears that you've added Nvidia Network Interface Cards (NICs) to both machines. In order not to butt our heads against the wall unnecessarily here I'd *strongly* recommend physically removing the extra NIC from each machine until this issue is removed, although I'm sure you'd rather pursue the troubleshooting steps from the MS support page concerning the 0x80070035 first. Personally I would remove the extra NIC's first, but that's your call of course. Two, or more, NIC's in the same box (whether as an actual NIC or an on-board adapter) can often be quite problematic once a connectivity issue arises, so removing one if not in use/essential to operations would be strongly recommended. Sorry, I should've picked up on that one sooner. :/
9) A partial capture of your ipconfig/all info is as follows:
Vista laptop
Physical Address. . . . . . . . . : 00-C0-A8-F3-84-86
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::8c01:29e1:409c:15c2%9(Preferred)
IPv4 Address. . . . . . . . . . . : 192.168.1.136(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1
DNS Servers . . . . . . . . . . . : 80.58.61.250
80.58.61.254 XP Desktop
Physical Address. . . . . . . . . : 00-03-C9-4E-F4-2A
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.1.34
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1
DHCP Server . . . . . . . . . . . : 192.168.1.1
DNS Servers . . . . . . . . . . . : 80.58.61.250
80.58.61.254
10) Good catches by jbennet and RLHenning - hopefully I would've seen the DHCP issue but I know essentially nothing about Vista - at least Vista specific - configurations/abilities, etc.
At this point, if I were experiencing the issues you're encountering, I'd follow-up on the MS support link first. If that didn't work I'd remove the secondary NIC's from both machines and then retry the MS support trouble shooting procedures. If I still couldn't connect both machines I'd bypass the router entirely and connect both machines directly to each other with a cross-over cable, and, once I had the two machines isloated from any external connection(s), I'd disable "anti-" software - anti-virus, anti-spam, "anti-intruder" (ie, firewall), etc. And if all that didn't work? I'd pick up knitting or basket weaving! :}....but talk to us first
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