I can not connect my laptop running windows 7 to my desktop runing windwos xp. Up to about a week ago it worked fine. I have been trying the last few days to find the problem to no avial. I can connect the windows xp to the windows 7 machine but not the other way around.

Hello, If you haven't already, please see this: http://windows.microsoft.com/en-us/windows7/Networking-home-computers-running-different-versions-of-WindowsEric

I am having the same problem as the original poster. This was working fine as of last week (week of 29 Mar 2010). Have any of the recent patches to Windows 7 affected this functionality? Basically... it was working, something changed (that I did not directly do), it now doesn't work. I'm trying to identify what changed. Thanks.

I discovered some additional issues last night while testing - I can no longer share local folders on my Windows 7 machine. (Access from other XP machines to the one I was trying to access work fine, so the issue is definitely on the Windows 7 laptop.) All of the services that have been referenced in related posts are running, all services are active on the interface (IPv4, IPv6, etc.). When I try to share a local folder, I have another Explorer window open up that says "Your folder cannot be shared." There are no entries in the Event log. I tried uninstalling/re-installing File/Print Sharing to no avail. It sounds like there may be something with this service that has been corrupted...? When I do a "net view" of my local machine from a CMD window, it looks OK (with nothing shared). When I try to view my XP box, I get a return code 53, stating that the remote network is unreachable. If I try to share a network drive via an Explorer window, I get a message with the error code 0x800704cf. I get the same results with either the wired or wireless interface. Any suggestions? The laptop is a Toshiba T135-S1305 with the OEM install if that matters at all. It also has Office 2007 installed and Microsoft updates automatically applied.

I continue to try the various recommandations to no avial. I can see and change the files on windows 7 system from my xp systems. I also can ping all the computers both 7 and xp from each other.

In case this helps... I was having a similar problem on a new laptop (Toshiba) with Windows 7 Home Premium using wifi. Accessing a share on an XP desktop "suddenly" stopped working. It appears the issue is related to the Microsoft Virtual WiFi Miniport Adapter, which was evidently installed with a driver update around the first week of April. Even though the adapter is disabled, it appears that any changes that you make to the settings on your "normal" wireless adapter also need made on this one. For me, this included enabling NetBIOS over TCP/IP (under IPv4 settings) and ensuring IPv6 was disabled. Again, THE INTERFACE IS DISABLED, but these changes still "magically" made my sharing work immediately.