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jrblues16
Posts: 1
Registered: ‎04-05-2007

IP Address Conflict

Does anybody have a fix for IP address conflicts? There's 2 laptops in the house and whenever both are in use there's an IP address conflict. I have both set to automatically obtain IP. I can usually set them to a set IP and that solves it, but I shouldn't have to do that. Anybody know why this might be happening to me?
 
Thanks,
toomanydonuts
Posts: 6,365
Registered: ‎09-16-2006

Re: IP Address Conflict

What router are you using?  Are any of the devices on your network set to fixed LAN IP addresses?  Which device(s)?  What address(es) are you using?
 
The most common cause for IP address conflicts is incorrectly using fixed LAN IP addresses.
 
With Linksys routers, a fixed (static) LAN IP addresses must be assigned in the device that is using the address.  So you need to enter the fixed address in the computer or printer, not in the router.
 
When using a Linksys router, any fixed LAN IP address must be outside the DHCP server range (typically 192.168.1.100 thru 192.168.1.149), and it cannot end in 0, 1,  or 255.
 
Therefore any fixed LAN IP address would normally need to be in the range of
192.168.1.2       thru 192.168.1.99  or
192.168.1.150  thru  192.168.1.254
assuming you are still using the default DHCP server range.
Rhoy10721
Posts: 32
Registered: ‎04-03-2007

Re: IP Address Conflict

I agree with the network administrator: toomanydonuts! However, he/she wasn't able to tell you how to check and fix your problem. Just do these steps:
 
Click start> control panel> network connection> right click on local area connection (for pcs that are wired with ethernet cable) or wireless network connection (for computers wirelessly connecting to the network> click properties> under general tab look for Internet protocol(tcp/ip), highlight it> then click properties> then choose from the following:
 
1. set all pcs to obtain an ip address automaitcally.
2. set all pcs to use static ip. to do so, choose "Use the following IP address", then type these information:
   - IP address: 192.168.1.5 (for the first pc, 192.168.1.6 for the second pc, and so on and so forth), or depending on your network's 1st, 2nd and 3rd octet of IP
   - Subnet Mask: will automatically be set to 255.255.255.0 when you click on its box
   - Default Gateway: 192.168.1.1, or depending on your network's 1st, 2nd and 3rd octet of IP
 
How to check router's 1st, 2nd and 3rd octet of IP:
 
Click start> run> type cmd (for win 2000 or xp) or command (for win ME, win 98, win 95)> type ipconfig (for win 2000 or xp) or winipcfg (for win ME, win 98, win 95)> then get your default gateway. the first 3 sets of number/s is are the 1st, 2nd and 3rd octet of IP of the router
 
I hope this helped...
sharkbyte
Posts: 1,330
Registered: ‎10-09-2006

Re: IP Address Conflict

Guys, he knows how to that already... when he said
 
"I can usually set them to a set IP and that solves it, but I shouldn't have to do that. Anybody know why this might be happening to me?" .........
 
So you don't have to tell him all over again how to assign static IP... anyway solution here might be to upgrade your routers firmware to the latest one.
twhTami
Posts: 1
Registered: ‎12-30-2007

Re: IP Address Conflict

Rhoy--
I know this is an old thread but I am glad you put the directions--these forums are used for searches and I don't speak "networking" but am going to have to learn.
 
I am having the same issue as this poster.  I used to get the IP address conflict error but now it just boots me off my laptop anytime my daughter signs in to the main computer that the router is connected to.
 
I am a complete newbie with network issues so speak like your talking to an idiot. 
 
I didn't even know how to check the box "obtain an IP address automatically"  but I think I figured that one out.  I went to Network connections and then right clicked on the local area connection on the main computer.  From there I chose Internet Protocol (TCP/IP) and then clicked properties.  On the general tab I chose the correct radio buttion . . "obtain an IP Address automatically".  You said to do that on all computers. 
 
But then I get confused at step 2.  I just picked obtain IP   .. . . when I choose the "use the following IP . . ." it takes off the "obtain an IP address automatically".  Why step number 1 if we are just going to change it?
 
Remember speaking to someone who doesn't speak "networking"
Rhoy10721
Posts: 32
Registered: ‎04-03-2007

Re: IP Address Conflict

Hi twhTami!
 
Those are 2 different options that you can choose from. Step 1 allows your router to give out the IP addresses to all of your computers, preventing an IP address to repeat on the other pc. Step 2 allows you to manually set a static IP on the pc so that you yourself will be sure that there will be no conflict.
 
There is one thing I forgot to include on my previous post... Setting a pc to "Use the Following IP Address" will automatically set your pc to "Use the following DNS servers". And you will also need to set the "Preferred DNS server" and " Alternate DNS server" these options are found right bellow the "Use the following ip address" option. Set the following:
 
Preferred DNS: 4.2.2.1
Alternate DNS: 4.2.2.2
 
These are universal DNS numbers.