pinging a computer in LAN adds (.net) to its computer name

[gignext]

hi all,

i m glad to find a forum like this to post my questions, and hope i'll get right solutions.

Recently i came across a peculiar problem in my office, some laptop running vista will have problem in pinging/connecting system in LAN using its system names, but can ping by its ip address. what i found is if i ping a system for ex. "comp1" it pings "comp1.net", but can ping/connect by its ip address with no problem and can access its shared folder. whatever system i ping with its system name it adds ".net" to its name and ping an external server in internet.

this is causing problem connecting outlook to exchange server and lot more. but this problem will last for 1day the next day its pinging to systems correctly. i had cleared dns cache, change the ip address, scan for viruses, but i could not figure out the cause of the problem.

help me to sought out this issue,

thanks in advance

[Milton.J]

There can be many reason behind this. In the computer can be pinged by IP address but the same if you try it by giving the name of computer you do not get any result. This can be due to Multiple connections like lan, wan, wireless, etc. Second this you are not able to see your computer on LAN. The solution can be this you will need to dowload NetBEUI. It is a tool which used to manage the network connectivity in a wide network. Otherwise try to flush your DNS. Give the command - C:>ipconfig /flushdns . Press enter.

[gignext]

thanks for replying.....

i had tried the flushdns command, even wireless NIC is diabled, but that didn't solved the problem, i just want to know the cause of the problem so that i can avoid such problem in the future. this problem appears occasionally that to in my boss laptop only. he wants the reason for this cause.i'm totally messed up hw come it can ping to an external system when i ping a local computer in my LAN.

i dont know how it is adding ".net" to the computer name that i supposed to ping, i have checked every possibilities(even looked at C:\WINNT\system32\drivers\etc\hosts file also) but could not find answer, sometimes they use vpn, but still that is also disabled while that problem appears.

i hope u could find the answer for this issue.....thanks in advance.

[Pikachoo]

go to the Control Panel, then Network Connections, right-click on Local Area Connection, and choose Properties. On the General tab, make sure that all the protocols such as Internet Protocol(TCP/IP) are installed and checked. Check the icmp settings of windows

Start>>Run>>firewall.cpl>>Advanced>>Click "Settings" under ICMP

the only option that should be checked is "Allow incoming echo request", hope this helps. You can do this by right-clicking on Local Area Connection, choosing Properties, and then selecting the Internet Protocol (TCP/IP) entry and choosing Properties. Then click Use the following IP address and type in an IP address that would work on your current network. Also choose Use the following DNS server addresses and type in the IP address of your router. Click OK and then OK again. After that, go back to that screen and choose Obtain and IP Address automatically for both and click OK.

[Fabkins]

Its possible that one of the machines on the network is incorrectly configured and thinks its on ".net" domain. Your machine is then getting the host and IP info from this machine. Track down the machine that is broadcasting this.

[gignext]

no it may not possible, i have configured static ip for all machines in the lan.than how come it will get ip config from other system. if u r correct how to traceout that machine.

thanks for reply, post any suggestions

[Fabkins]

Configuring static IPs is all well and good but WHERE is it resolving the names from. If it is alternating between having a .net and a non .ne domain I suggest it is getting the named resolved from more than one place.

Basically, a system will resolve a name (resolve means look up a name and convert it to an IP) through different ways. In no particular order:

- WINNS /NetBios
- DNS
- Local host files

The problem is likely to be with how WINS work. Unless you have a dedicated WINS server or DNS server, then some machine on the network will decide it will deliver name resolution for WINS for you. The system is great at home and small offices , people call their machines funny names and you all auto-discover each other.

However, because someone any machine can be a WINS server (unless you have dedicated one) then you are at the mercy of what that machine think your name really is. A common issue is if you change IP and but that machine keeps telling everyone you got the old IP then you find you can never connect to that machine by name.

I suspect you have the same issue. You have one machine that is broadcasting that its domain is .NET and its thinking that every machine on the network is .NET.

The EVEN worse problem with this system, is because its rumour based , it takes a while to get incorrect entries off.

As I said, CHECK to see if any of the machines think they are on a .NET domain. I *believe* that could be your issue.

To check each machine is a bit of a nuisance but here is what you do:

Goto the "Local Area Connection" you will get a whole list of services , ie Client for Microsoft Netowrk, File and Printer sharing, Internet Protocol, etc.

Choose "Internet Protocol Version 4"

I guess you've fixed the IPs here, but click on "Advanced.."

In Advanced check the "DNS" entry to see that no machine has "Append these DNS suffixes". If one has ".NET" in it then thats your bad boy.

If you have have dedicated WINS or DNS server of course, could be something different. But as you been setting IP addresses by hand , I suspect not.