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Claws224
Claws224, IEEE Network Engineer
Category: Networking
Satisfied Customers: 5182
Experience:  IEEE, Microsoft
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One of my computers keeps losing its IP address and then I

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One of my computers keeps losing its IP address and then I cannot ping between it and the other computers. Rebooting fixes it for a while. It is a desktop, so it is not powering down or anything like that. I have to reboot a lot, and it is a problem as I like to file-share and I use software with remote licenses. I am using a Linksys Wireless-N Home router, serial 35179481, connected by Ethernet cable to two computers and running a third one wirelessly. Only one of the cable-wired computers gives trouble. the others are laptops and are always OK. I chatted with the Comcast rep and they said it is definitely not possible that it's their problem.

Hi,

 

Can you tell us if the computer gets its IP from the router or did you give the IP address to the machine?

 

Thanks

Eric

Customer: replied 7 years ago.
Hi - I did not take any special steps when I bought and installed the router, so I guess the computers are getting their IP's from the router. This same problem happened, sporadically, with 3 different routers. It's always the same computer that has trouble (Vostro 64-bit running Windows XP 64-bit).

Ok,

 

On your machine that you are using to talk to me can you click start then run and type CMD into the Run box and hit Ok to open a DOS window.

 

When the window opens can you then type ipconfig /all and hit enter then tell me what your machine lists for IP Address, Subnet Mask, Default Gateway and DNS

 

Thanks

Eric

Customer: replied 7 years ago.

On the desktop computer that is giving me trouble,

IP address 192.168.1.101

Subnet mask 255.255.255.0

Default Gateway 192.168.1.1

DNS Servers

68.87.77.134

68.87.72.134

fec0:0:0:ffff::1%1

ditto 2%1

ditto 3%1

 

On the laptop computer that I am using to talk to you now,

IP address 192.168.1.100

Subnet mask 255.255.255.0

Default gateway 192.168.1.1

DHCP server 192.168.1.1

DNS servers 68.87.77.134 and 68.87.72.134

 

At the moment, the computers can ping each other.

Ok,

 

Is the problem machine currently online?

 

Thanks

Customer: replied 7 years ago.
yes

Ok,

 

Can you go to the problem machine and click start then control panel and open Network connections.


When it opens can you double click the Local Area Connection and then select TCP/IP and click Properties.

 

Once the properties window opens can you choose specify IP address and enter the following:-

IP address 192.168.1.175

Subnet mask 255.255.255.0

Default Gateway 192.168.1.1

 

Next can you check the specify DNS option and enter the following:-

 

DNS 1 68.87.77.134

DNS 2 68.87.72.134

 

Once that is all entered can you then save the change and restart that machine and let me know if it will get online when it restarts

 

Thanks

eric

Claws224 and 2 other Networking Specialists are ready to help you
Customer: replied 7 years ago.
Excellent, thanks! It goes online OK. I dont know for sure if its cured until I work with it for a couple of days, but the solution makes perfect sense. Tjhis has been bugging me for months! Thanks.

Ok,

 

Basically what you just did is set a Static IP address onto the machine so that it will never change unless you change it yourself.

 

Just run it for a couple of days and make sure it is all good and let me know back in this thread if you have any issues

 

Thanks

Eric

Customer: replied 7 years ago.

Hi, claws224 - Unfortunately the same thing happened again a couple of days ago, so I had to reboot and then OK. Today the computer was unable to access the Internet, so I rebooted again and now OK. The IP address, DNS etc is still as I set it before. You said to respond on this thread if there were still problems. Is there some information I should check?

 

Ok,

 

When it happened did you get an error on your machine?

 

Thanks

Customer: replied 7 years ago.
No, there was no error message of any kind. The connection showed no problem and said "Windows does not detect a problem with this connection".

Ok,

 

Were you using any other computers or network devices before this happened?

 

Thanks

Customer: replied 7 years ago.

Yes, I was using my laptop, which also has an Ethernet cable to the router. Also I took it on a trip and re-connected it on my return. I cant remember if this has always been the case just before the problem arose. My wife's laptop is also in use. It is a Mac (the other two are IBM type), but the problem was the same when she also had a Dell laptop.

 

Ok,

 

It sounds like an IP conflict which could happen if something elese is trying to use the same ip as the one we assigned.

 

If you could open the TCP/IP window and change your static IP to 192.168.1.75 then save it and just keep an eye on it for a week or so and let me know if you have any more trouble out of it

 

Thanks


Eric

Customer: replied 7 years ago.
OK thanks - will let you know.

Ok,

 

Just let me know back here if you have any issues with it

 

Thanks

Customer: replied 7 years ago.

It's happened again... Seems like whenever I unhitch my laptop (Dell) from the ethernet cable, and take it on a trip, and return, the desktop loses its Internet connection. The laptop is currently using IP address .100 and my wife's laptop is using .102, both automatically obtained, while the desktop is now set manually to use .75, so it doesnt seem that they are trying to use the same IP address?

 

Hmmm,

 

Do you have any other wireles or wired devices, Such as iPhones or a Tivo box?

 

Thanks

Customer: replied 7 years ago.
no, none

Strange,

 

If you shut everything downthen power up the desktop first then power up the others does everything work correctly?

 

Thanks

Customer: replied 7 years ago.
Yes - if I shut down the desktop and restart it, everything is fine.

Ok,

 

Can you run the tool on this Microsoft site and let me know what happens http://support.microsoft.com/kb/299357

 

Thanks

Eric

Customer: replied 7 years ago.
I ran it and it said it had run the FixIt, to re-set the TCP/IP, but no error messages or anything. It said to restart, so I am restarting. Restarted OK, and the Internet seems to work fine. It is now obtaining IP address automatically. I will let you know if it does the same thing again. Thanks

Ok,

 

Keep me posted.

 

Thanks

Customer: replied 7 years ago.
Done it again... this time it was overnight, and the desktop lost its Internet connection, although I didnt undo the laptop. My wife's Mac powers off after a while but my laptop just turns off the screen.