Networking problems between two computers

October 12, 2005 8:30 AM

Home networking problems between two computers.

I've got a wireless router through which my laptop connects to the Internet. My desktop is wired to the router. I'm running Windows XP on both, and I had a decent network running between the two which allowed me to modify files inside folders I designated as shared. Recently, and seemingly completely out of the blue, both computers have stopped acknowleding shared folders residing on the other computer. I was using the laptop as secondary storage, so it's really becoming a hassle to not be able to move files on there easily. Any ideas as to what could have caused this?

posted by jimmy to computers & internet (19 comments total)

Do you use a software firewall, like Zonealarm? I've had to turn off Z-A, because its latest upgrade disabled my network on my XP computer.
posted by Kirth Gerson at 8:50 AM on October 12, 2005

Has a recent XP security patch turned on the firewall? The default settings would block file sharing, methinks.
posted by bachelor#3 at 8:50 AM on October 12, 2005

The Windows firewall doesn't block my file sharing. I was using Zonealarm instead, and had the Windows firewall turned off, but when I turned off Z-A, I enabled the Windows one, and now have no trouble sharing files.
posted by Kirth Gerson at 10:43 AM on October 12, 2005

If firewalls aren't the problem, it may be the more stringent security requirements of Service Pack 2. You need to have a user account on both computers with the same name and password. I find this a pain, but I've had this fix work on two different LANs now.
posted by Yogurt at 11:24 AM on October 12, 2005

I have a wire based home network, and had serious problems getting everything to work, until I turned of Windows Firewall.
Seriously, shut it off. It is blocking your sharing, even if you think it isn't.
posted by signal at 2:00 PM on October 12, 2005

I'm not using ZoneAlarm, and I turned off Windows Firewall on the laptop, but it doesn't seem to have changed anything.

In fact, now it's not displaying ANY of the other workgroups, which seems to just happen randomly.
posted by jimmy at 2:17 PM on October 12, 2005

I just went through this setting up my network. Like the others, my problem was with the firewall (Norton Internet Security). You don't have to completely disable it though, just set it up to explicitly "trust" the IPs of all of the computers on the network. I believe this was through the "Exceptions" option.

You may already be aware of this, of course, since it sounds like you had things working just fine for a while. But any auto updates (or ISP funkiness) may have changed your settings. I'd check to make sure your exceptions settings haven't reverted to defaults, and/or that your IPs haven't changed.
posted by It's Raining Florence Henderson at 2:19 PM on October 12, 2005

I should clarify that I don't think that last bit happened as a result of anything I did following your suggestions; it just happens to be another oddity that I've been seeing off and on since this problem started. I should have mentioned it to begin with.
posted by jimmy at 2:21 PM on October 12, 2005

On preview, the firewall messing you up is probably on your desktop, not your laptop. Or, at least, that was the case with me.
posted by It's Raining Florence Henderson at 2:22 PM on October 12, 2005

As far as I can tell, there's no option in Windows Firewall to allow exceptions from specific IP ranges. Just programs.
posted by jimmy at 2:54 PM on October 12, 2005

I think you can also open specific port exceptions and limit them to specific IPs using the Change Scope option from the same location (described here). Can't guaranty that there is no additional security risk involved, as I'm not a security professional, but it doesn't sound any more threatening than any other IP specific exception.

Of course it might be a good idea to temporarily disable Windows Firewall on your desktop first, to check if that is actually causing your problems.
posted by It's Raining Florence Henderson at 3:15 PM on October 12, 2005

I've turned Windows Firewall off on both, now, with no effect.
posted by jimmy at 3:19 PM on October 12, 2005

Strange. Not sure what else would have hosed your settings like that. Are there any other security apps on the computer that might be interfering? Norton? McAffee?

If not, I guess your best bet at this point would be to walk through the MS home networking troubleshooting guide, and then maybe call them or try their support newsgroup.

Good luck!
posted by It's Raining Florence Henderson at 4:12 PM on October 12, 2005

Have you installed the MS Anti-spyware program? I have seen this completely screw up network sharing when it asked a question and the user carried out the recommended response (which I can't now remember) and that blocked all sharing between computers on the network, although they could still see them in the workgroup.
posted by dg at 5:41 PM on October 12, 2005

Oh, man, that might be it. I installed that recently on both computers. Do you know if simply uninstalling it is reported to fix the problem?
posted by jimmy at 5:48 PM on October 12, 2005

No idea what the fix is, but I suspect that uninstalling may not be it, because the problem is not the software itself, but the changes that it has made to the system that cause the probem. Have you tried a system restore?
posted by dg at 6:15 PM on October 12, 2005

No, I haven't. I'm not even sure how to go about doing that.
posted by jimmy at 6:43 PM on October 12, 2005

All right, I managed to restore to a point previous to the AntiSpyware installs, to no avail. I'm at a total loss, now.
posted by jimmy at 7:47 PM on October 12, 2005

Can you ping from one computer to the other?
posted by signal at 8:52 PM on October 12, 2005