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zed
2005-04-28, 01:58 PM
My GB-PVR system works great, no problems. However, I'm having a Windows networking problem that I don't understand and thought that perhaps some of you gurus wouold have some suggestions.

I have a lan at home with five Windows computers on it. I have a router that accesses the internet thru a cable box. All the machines have good access to the outside world...no problems there. The issue is that the machines can't see each other to share files, a printer, etc. I can ping all the boxes from each other and the My Network Places sees my workgroup but no machines in it. The other puzzling thing is that it was working fine up to a few days ago. I haven't changed anything that I know of. They are all running the Windows client and server with sharing enable but it doesn't work. I'm very puzzled by it, esp. since it's been working fine. I'm running XP on all the boxes, Pro on two and Home on the others. They're all at SP2 with the latest upgrades. I suspect that a service is not started but I don't know which ones should be running. Any suggestions will be appreciated.

stefan
2005-04-28, 02:07 PM
I had this problem, too. I don't remember exactly how I fixed it, but it had to do with NetBIOS settings. I'm not at home now, so I can't check it for you, but:
Go to network connections and open your network connection and click "properties".
Choose Internet Connection (TCP/IP) and click properties.
On the "general tab" click advanced.
The NETBios settings are under the "WINS" tab. I think you need to have NETBios enabled, but I'm not sure. Fiddle around and try =)

reboot
2005-04-28, 03:54 PM
I fixed mine very simply. Having a mix of XP Pro, Home, 98, and 98SE on the LAN, the best solution I found, was to install NETBEUI protocall on all boxes.
It's "invisible" to the internet, so that portion of TCP/IP is not touched at all, yet sharing is maintained perfectly.
To install in XP, put in the XP CD, go into Networking, add, protocall, and browse the CD to Extras, MS, Network, netbeui.
The fact that XP boxes cannot seem to maintain a TCP/IP LAN for more than a week, totally pissed me off. One small change on one machine, and the whole thing goes south. Install netbeui, and it's been stable for over 2 years.

j3flight
2005-04-28, 04:42 PM
It's not a big deal to keep the windows workgroup stuff working over TCP/IP on XP or other platforms, you just have to follow a few rules.

The workgroup listing and local naming is kept up with broadcasts. When a machine connects to the network, it broadcasts its presence to everyone else and grabs the local machine listing from the master browser (who is sort of randomly elected).

So, you have to make sure every machine is accepting broadcasts from other machines on your LAN - some VPN software screws this up and I've seen other stuff get in the way as well. Some firewalls will say they open ports, but then still block the broadcasts, duh.

These broadcasts are made on ports 135-139 so make sure they are completely open.

TROUBLSHOOTING:
Turn off all software firewalls first! They are the biggest cause of NetBIOS problems.

Next...
Ping the machine you think has issues. If you're successful, you know you at least have network connectivity. If you're not successful, get to work fixing that.

Next...
Go to Start-Run and type \\<ip_address>
That should get you a share listing of that machine. If not, then ports 135-139 are not open on that particular machine like they should be. (Or file sharing isn't even turned on)

Next...
Go to Start-Run and type \\<machine_name>
That should get you the same result as above. If not, it means that you're not retrieving a workgroup listing and indicates the correct ports are not open on the machine you're sitting at.

Next...
Assuming all of the above are working, after the machine has been connected to the network for about 15 minutes, check the workgroup listing. It should be populated. If not, then there is probably an issue with broadcasts not being received by the machine you're sitting at.

Jason

zed
2005-04-29, 02:48 AM
Thanks to all for the input. I played around a little and here's the situation...

- NetBIOS is enabled on all the machines
- I can ping all of them from each other
- Entering \\computername in Run immediately connects to the named machine. This works from all the machines to the others and all the shares on the target computer are then available.
- In 'My Network Places' I can select Entire Network, then Microsoft Windows Network, than after a minute or so I get the icon for my home workgroup (imaginatively named 'Home'), then I click on the icon and after a couple minutes I get a popup box that says "Home is not accessible. You might not have permssion to use this network resource. ... The list of servers for this workgroup is not currently available."
- Client for Microsoft Networks and File & Priner Sharing for Microsoft Networks is enable on all the machines
- All the machines have at least something shared
- They're all connected to a 10/100 switch (actually, three switches linked together but it doesn't seem to matter which switch...same result for all)
- This all worked just fine a few days ago

I'm really at a loss to see what the problem is. I'd guess that for some reason they're not broadcasting their existence. I assume there's a service that handles the broadcasting and the collecting thereof...anyone know what they are? All the services that I'd guess would have something to do with it are enabled but I don't know if I'm missing something. I've been running a network for years, since the thin-net (coax) days. I don't remember ever having this kind of problem. I'm getting a lot of flak from the users (wife & kids) because they can't print to the shared printer and are trying to get out term papers. Any advice will be greatly appreciated.

j3flight
2005-04-29, 06:34 AM
My guess is that you've installed some sort of firewall or enabled the windows xp firewall without enabling file sharing, or something along those lines..

You might also try verifying that the services are running properly:

Server
Workstation
Computer Browser

A link for you...
http://www.experts-exchange.com/Operating_Systems/WinXP/Q_21046974.html

On that page are more links to help. In my experience, it almost always comes down to some POS software firewall! :)

Jason

wtg
2005-04-29, 01:00 PM
Zed,

The software firewall angle has already been covered so I won't go there.

Is it possible you turned on some kind of firewall or packet filtering on your router? I don't know exactly what kind of traffic file and print sharing create other than I do know that they send out notices to the network to broadcast that they are available. Is it possible these broadcasts are being filtered by some setting on your router, either by design or bug in the router itself?

If you don't know one way or the other you can try hooking up two computers directly together, without a router. Either use a simple switch if you have one or a cross-over cable. Some network cards (or is it the drivers?) are smart enough that you don't even need a crossover cable, but it's probably better to use one. If you find the two PCs connected directly can see each other's shared resources then you can figure it's probably the router.

Good luck. Sounds frustrating. =(

zed
2005-04-29, 04:57 PM
Thanks for all the suggestions.

The Computer Browser service was not running so I started it on all the sysems. That seemed to help the printer sharing problem (which is the hot button for the moment). It was set to Automatic but was not running. I thought that Automatic meant that it started at boot-up??

No firewalls are enabled on any of the machines so I don't think it's that.

I can see shares fine using the \\computername in the Run box so I don't think anything is blocking the traffic. All the boxes are connected via switches and switches shouldn't block anything. All the IP's are in the 192.168.0.0 range with netmask of 255.255.255.0 so no lan traffic should be sent to the router. They're all in the same workgroup. I guess the real question is why the shares don't show in My Network Places.

At any rate, it seems to be under control for now. I'll dink with it some more but it's more of an irritation and a mystery than anything. It should work. One of the incomprehensible mysteries of the Microsoft world, I guess. When I have time I'll check the MS Knowledge Base. If I figure it out, I'll let you all know.

I'd be tempted to switch to Linux (or more likely, FreeBSD), but then I wouldn't be able to run GB-PVR... :D

wtg
2005-04-29, 05:54 PM
Thanks for all the suggestions.

The Computer Browser service was not running so I started it on all the sysems. That seemed to help the printer sharing problem (which is the hot button for the moment). It was set to Automatic but was not running. I thought that Automatic meant that it started at boot-up??

No firewalls are enabled on any of the machines so I don't think it's that.

I can see shares fine using the \\computername in the Run box so I don't think anything is blocking the traffic. All the boxes are connected via switches and switches shouldn't block anything. All the IP's are in the 192.168.0.0 range with netmask of 255.255.255.0 so no lan traffic should be sent to the router. They're all in the same workgroup. I guess the real question is why the shares don't show in My Network Places.


The Computer Browser service is a big step obviously.

By the way, how are your shares setup? You aren't just sharing from the root of the drive are you? Those shares get names like C$, D$, etc... and share names with a $ on the end CANNOT be viewed through the browser. They are hidden administrative shares that you can connect to using \\comp\c$ syntax, map drives, etc... but they will never appear in the network browser.

I've been confused by this before... is that it perhaps?

j3flight
2005-04-30, 08:16 AM
Also, not to insult your intelligence, but make sure you're clicking "view workgroup computers" from within my network places.

My network places is just a catch all area where it keeps links to places you've been. It DOES NOT list the available shares on your network, you have to go to the workgroup listing like i said above.

Sorry if you know that already, i've had so many people get confused by that.

Jason