Vista - How to connect XP with Vista on a Network?

I While ago i connected My xp pc [client] to my vista pc, but just recently my xp PC just disappeared from the network, i tried reconnecting it back by following some guides that i found on Google but still i got nothing, So far My Vista pc can only see the xp PC trough the network map, but when i click on network it doesn't appear at all. I dont know if im doing something wrong or if one of my PC's is causing it. This is what i tried to reconnect them again so far:

XP:
1. Control panel > Network and internet connections > set up or change your home or small office network > run trough wizard name my PC and Workgroup name.

2. Right click my C: drive > sharing and security.. > select* share this folder.

Vista:
1. Turn on: Network discovery, File sharing, public folder sharing.
Turn off: Password protected sharing.

2. Right click* Computer > properties > change settings [under "PC name, domain...] > change workgroup name to same name as XP's.

If you are behind a router try killing all firewall and av protection until you get it working. Another hint is just use the already shared folders. all users documents on XP and Public on Vista. At least until those work consistently. Then you can usually share other folders.

I think you have to get it to like you first. So you have to sneak up on it.

Yeah im behind a Liknksys WRT54G Router/switch, and i was sharing files just fine while using my anti-virus [Avast], im gonna turn it off and try without it though, i haven't tried the shared folder but i doubt itll work since both Pc cant see each other. I still give it a try though.

Reading your first post over again I think I see more what you mean. It seems like something got corrupted. If the same drivers are there and there are no device conflicts, network settings seem the same, router settings etc. then my first guess would be something in the registry. But that's just guesswork. First divide in trouble-shooting is always hardware/software. I'd do some kind of checking to eliminate the hardware as possibility first. If something all of a sudden goes bad and you didn't have a system lockup or power failure or otherwise hose things that would make me check out the hardware as much as possible first.

After that I'd look for stuff dependent on the registry.

Mixed windows flavors is always a pain. Used to be one machine was the "Master Browser" and if you didn't boot it first, nothing worked right. I guess stuff is a little different now but I'm not sure how much.

Can the two machines ping each other by name? Can they ping by IP?

Can you connect successfully in both directions using UNC (Universal Naming Convention): start, run, \\OtherPcName\ValidShareName ?

There's no point troubleshooting "net neighborhood" issues until all that works successfully.

I dont know how to ping by IP, sry im just noobish at networking =\, and i dont quiet get the second part, should i just go to run and then type " \\*vista's pc name*\ValidShareName [leave this alone?]

i dont quiet remember the day that this happened but i do remember that it was either after a restart, or while just browsing abit trough the internet on the xp pc. Im gonna try to do a couple of updates[OS & driver], and see what hapens after i rly think the Problem is coming from the XP pc since my vista pc can detect other pc's [vista pcs anyways].

To ping, open up a CMD prompt on each machine, type IPCONFIG so that you can see the IP address in each case. For example, let's say that the vista machine is called "bob" and that its IP address is 192.168.0.5. From XP:

ping bob
ping 192.168.0.5

And vice versa. It's the responses to those commands which are significant. If they appear to work, try:

<start>, <run>, \\bob

If that works and you see a window pop up with a list of some shares or perhaps printers shared by the vista machine ("bob"), then basic connectivity is working. Otherwise, there's no point troubleshooting more complex functionality yet.

Alright, i pinged both pc's [one to another] and no problem, each pc can see each other's ping i just noticed though that i gotta do it by ip address like type "ping 192.168.1.177", but if i do it like "ping bob" it wont work, same with xp, i also did the Start > Run > \\THX-PC [my pc's name] from XP and nothing just got an error same from vista.

Failing to ping by name while ping-by-IP works is somewhat odd for a local LAN setup. Make sure that all firewalls on both machines are disabled while you're troubleshooting, then turn them back on when you're done and check whether that made any difference.

Also, what happens when you UNC to the IP address of the other machine, for example:

<start>, <run>, \\192.168.0.5

I tried it all and it still didn't work so i got frustrated and decided just to do a system restore on the XP PC as a last resort and it worked, the PC once again appeared on the network, so apparently something was wrong with the XP pc.

-Thanks alot for your help H2SO4 and everyone else .