XP and Windows 7 PCs no longer on speaking terms

System: an XP PC and a PC recently upgraded from XP to Windows 7. I had no problem connecting the two (went kind of automagically, to be honest), and also could share folders both ways.
This morning, however, the Win7 PC no longer sees the XP machine, and while the XP PC still shows the other one in its workgroup it can no longer access it. I didn't change any networking settings(!). Both PCs are still member of the same workgroup.

Question: how can I set up communication between an XP and Win7 PC?

edit
Seems I was a bit too quick with my reboot comment. The connection was lost again, and this time didn't restore upon rebooting. I can ping the other computer, though. Annoying! Any help will be greatly appreciated with upvotes and possibly accepting answer :-)

stevenvh

Posted 2011-11-08T12:20:40.987

Reputation: 1 033

"solved" by rebooting. I still have the feeling that this is not the proper answer, nor a proper solution. – stevenvh – 2011-11-08T15:07:45.927

Something to try if it happens again, see if they communicate if you type the IP address directly into the explorer address bar? (ie on machine 2 type machine 1's IP address \192.168.0.1) – HaydnWVN – 2011-11-08T16:06:44.357

@HaydnWVN - typing the IP address directly in the explorer address bar results in a timeout error (cannot connect). I can ping the other PC, though. – stevenvh – 2011-11-08T18:21:55.560

Are the machine names the same? Are they on the same subnet? And same subnet mask? And to confirm - you have files/folders shared on the Windows 7 PC? – HaydnWVN – 2011-11-09T10:09:00.517

1@HaydnWVN - They have different names. They're on the same subnet (192.168.1.*), and have the same subnet mask (255.255.255.0). I have folders shared with "full control" to "everyone", but that's of little use if the other PC doesn't show on the network in the first place :-(. I might have thought there's something basic missing, but it did work after installation, and I didn't change any of the network settings. Thanks for your thoughts. – stevenvh – 2011-11-09T10:23:32.103

Answers

I think that I found the culprit. Under

crumbs

there's

Homegroup connections option

I set it to the current settings, but when I checked it had changed to the (default?) "homegroup" option. I'm absolutely, positively, certain that I did not reset it (getting slightly excited :-)). It reminds me of the Windows 2000 days, when settings could also change without any reason.
I hope it stays the way it is now. At least I know where to look, if the connection fails again. Have others also experienced unwanted changes to system settings in Windows 7? Or know of system or application software which makes these changes?

stevenvh

Posted 2011-11-08T12:20:40.987

Reputation: 1 033

404 for me on those images, but glad you've at least tracked down where the problem is occuring! Thanks for the +1 and well done for solving it yourself! :) – HaydnWVN – 2011-11-09T11:54:35.520

1@HaydnWVN - The image server seems to have suffered from hickups, but it should be solved – stevenvh – 2011-11-09T12:01:22.997

You will need to add the username+password used on the XP PC to the Users list on the Windows 7 PC for it to be able to access any of its resources (files, printer etc).

HaydnWVN

Posted 2011-11-08T12:20:40.987

Reputation: 3 192

1@stevenvh did your firewall get turned on after a windows update? I have had this happen before. – Supercereal – 2011-11-08T14:25:05.183

Saw a similar 'issue' here when phasing out old XP machines and replacing with new Windows 7 where we had to flush the DNS on the Ubuntu (+samba) fileserver for the couple of machines which where using the same IP's (We don't run DHCP). Replacing old Windows 2000's we had no problem. – HaydnWVN – 2011-11-08T16:08:24.417

@HaydnWVN - +1 for your help and for being close; see my answer. Thanks. – stevenvh – 2011-11-09T11:22:31.703