Windows PRO XP TCP/IP

[jcg]

Hi

I'm writting from Mexico and I have this problem:

I have 3 or 4 machines with Windows XP PRO and I can not ping among them.

they have ip address like this

192.168.1.3/255.255.255.0
192.168.1.4/255.255.255.0
192.168.1.5/255.255.255.0
192.168.1.6/255.255.255.0


everything seems SO simply, that's why I'm so confuse;

AND to make things worst I have an NT 4.0 with IP 192.168.1.1 and ALL the XP prof machines CAN ping it !!!

Any ideas?

thxs

 

[John Lewis]

Just read everything again. I missed earlier that you were able to ping NT from XP but not XP from NT. That eliminates the hub or switch (at least those two ports) and those cables as a problem, although in the process of moving things for testing you could have damaged a cable. Instinct says that is not the problem.

Are you sure the XP firewall is turned off? Double (or triple?) check.

Second place to look would be TCP/IP on the XP machine. Sorry, should have tried this first. On the XP machine, type 'ping 127.0.0.1'. You should see 4 good replies with a time < 10ms. 127.0.0.1 is the loopback interface for all (almost) machines with TCP/IP installed. If it doesn't work, you have real problems with TCP/IP.

I would also bring the NT machine back into the mix. It may or may not cause problems when it is time to work with issues other than core TCP/IP, but since it worked (at least partially) before, it could be valuable in finding the real source of your problem.

 

[bcastner]

mhkwood,

He's pulling a full DHCP package from both XP boxes from the Linksys router used as a test. Both XPs end up on the same subnet.

He can ping the router from both XP's.

There are no firewalls.

The Linksys router is not blocking WAN requests.

Just very, very, very strange.

 

[John Lewis]

bcastner,

Had to go back and read everything again.

Just to clarify my thinking here . . .

DHCP can work with broken TCP/IP, but not with broken cables (or other hardware). Looks like it is working here, so hardware is out of the picture.

I still don't see where he (we're assuming jcg is he) can ping the router. I did see a couple of references to being able to ping a NT box, which has since been removed. NT box can't ping the XP boxes. Seems the XP boxes can generate a ping request and receive a reply, but either cannot receive a request or generate a reply.

Either TCP/IP is broken somewhere, or the requests to the XP machines are being blocked. jcg has stated that the firewall (technically TCP/IP filtering) built into the XP TCP/IP is turned off. I would check again, as it could certainly cause this problem.

The other possibility that comes to mind immediatly is that TCP/IP is broken, although it does seem odd that it is broken on all of these machines. On the other hand, XP is very picky about network protocols. You are supposed to use TCP/IP and nothing else (not officially, of course). The way TCP/IP is tied into the OS causes some problems, especially when other protocols are added/changed/removed. Seems there was IPX/SPX involved at one time, and that could cause some not so nice things.

Having said that, the fix is not pretty. The official MS fixes work about 40% of the time (sometimes make things worse). So, best to make darn sure it's broke first. If the loopback flies, I would tend to look around a little more first.

But yes, any way you look at it, very strange.

 

[bcastner]

jcg,

I am going to ask you to download a utility that will rebuild your Winsock service. This more exhaustively will purge the Winsock service and rebuild it with a clean XP/SP1 registry image of 24 registry keys, flush all stored routing tables, ARP caches, etc.. forces a Device Manager reload of NIC drivers, and then does an netsh ip reset.

After the reboot check your TCP/IP property sheet as it will be back to the Windows default state.

Then try the ping tests again.

The utility can be found here:

http://members.shaw.ca/techcd/VB_Projects/WinsockFix.zip

Let us know the results of the ping tests after the repair.

 

[bcastner]

Also, if you have a cross-over cable handy, could you also do a series of ping tests with the two PCs connected directly. Thanks.

 

[gl3nc]

I am now getting the same issue with Windows XP on a Toshiba Satellite Pro.
I can connect to other machines fine, e.g. web browsing, terminal services, outlook.
However if I ping from my machine to Machine B I get a response o.k.
If I then Ping from Machine B to my machine I get no response!

I have even tried a cross over between the two machines, but it is still the same.

Anyone got any more ideas ?

 

[jcg]

I've been out so I'm going to start doing what you asked me to do, bcastner, right now.

But first I want to tell you that both machines got their IP from the LinkSys router ( 192.168.1.xxx ) and from both I could ping the LinkSys.

As a matter of fact the linksys has a real IP and I can surf in the internet from both machines ( I've been posting from one of the two machines ).

BUT I don't think the LinkSys is the problem because I made tests without the LinkSys and using fixed IP's ( 192.168.1.xxx/255.255.255.0 ).

They could not ping each other neither.

If I turned on the NT both machines could ping the NT but you could not ping the machines from the NT.

Also, I turned on a machine with windows 98 and you could ping the xp pros BOTH ways. But you could not ping among the xp pros. Obviously, you can ping from 98 to NT both ways.

Everything is connected to the same hub.

I also think that using IPX/SPX and TCP/IP causes problems.

But why does the xp pros got ip's from a dhcp, ping the linksys, surf the internet, and can not ping each other ??

 

[bcastner]

For some reason this last week has seen a spate of these ping failures and I am baffled by them.

As mhkwood was insisting earlier, a ping failure is a very low-level connectivity issue: it is either a bad nic, a bad nic driver, a bad cable, a bad cable plant and connection hardware, or a firewall issue.

if you ping 127.0.0.1 and get no response, you have a bad nic, bad drivers, or corruption in your Winsock and router service tables.

if you can ping B but not be pinged yourself by B, it is likely a firewall issue on your end.

jcg has a situation that is completely baffling. There is no reason on earth connected to the Linksys that A and B cannot ping each other with Block Wan requests disabled.

The only thing some web searching turned up as a relatively new issue in this regard is PC-Illan, an anti-virus program that also installs a small firewall. This in the last two months has caught many. It can be disabled in the software but is installed by default. But I just see not XP hotfix issue or any other XP application causing such a flurry of connectivity issues.

I am truely baffled.

 

[jpm121]

bcast, it's a long shot but possibly something risidual in the route tables on the PCs?

The block WAN request shouldn't matter either way -- this is all happening on the LAN side of the router, and the WAN port doesn't even enter into the equation.

 

[bcastner]

jmp121,

Should only have routes set by hand with a /p switch, everything else should be rebuilt at boot.

I do worry about this side of it though. The WinsockFix utility I cited earlier will rebuild the table pointers.

 

[k4wjr]

I have seen very similar problems on several different workgroups consisting of XP, 2000, NT 4.0, 98 and 95 PCs. All basically have this problem. I will describe how one of the workgroups acts. I have not yet figured out why this happens.

I have three PCs connected through a hub in a Workgroup configuration. The three PCs have a physical connection that is easily verified. There is no connection to anything else. Just the PCs connected through a hub.

Two of the PCs run Windows 95, and one runs Windows XP.

All three machines have static TCP/IP addresses in the same addressing range, the same subnet mask and the same workgroup name.

All three machines have their C drives shared for full access.

The Windows XP PC can ping both of the Windows 95 PCs, and the Windows 95 PCs can ping each other; however, the Windows 95 PCs CANNOT ping the Windows XP PC. I get the same results when the other machines are running 2000, NT 4.0, 98 and/or 95.

The Windows 95 PCs can map drives on each other but not on the XP machine.

When I try to map a drive on the Windows XP PC to either Windows 95 PC by typing the UNC path to the share, Windows XP says the path could not be found. If I then try to browse to the shares, Windows XP shows me the PCs, but will not show me any shares on them. If I right click on the Windows 95 PCs and choose “Explore,” I receive an error stating that I might not have permission to access the network resource.

 

[jcg]

And the bad boy IS:


PC-CILLIN

you were right, it installs a firewall and when I desinstalled it everything started to work

THANKS A LOT !!!!!

 

[bcastner]

Wait a minute....

I asked about firewalls and anti-virus, and brought up PC-Illan specificly.

Quote: &quot;
jcg has a situation that is completely baffling. There is no reason on earth connected to the Linksys that A and B cannot ping each other with Block Wan requests disabled.

The only thing some web searching turned up as a relatively new issue in this regard is PC-Illan, an anti-virus program that also installs a small firewall. This in the last two months has caught many. It can be disabled in the software but is installed by default.&quot;

You swore to me no firewalls.

You are a naughty, naughty boy.

Warning to PC-Illan users: this program currently installs a small firewall. It will deny you DHCP services and return APIPA IP address 169.x.x.x, it will block pings to your workstation, it will block Netbios traffic on your LAN.

If you use this software on a LAN setting turn off the default firewall.