Hi all,

I have a wireless network with a ADSL modem/router and a wireless DLink
'Range Extender'.

When I run this I get: 'Windows - System Error. There is an IP-adressin
conflict with another system on the network'.
What does this mean? How can I fix it?

Kent J.

It means what it says - the IP address your computer is trying to use is
already assigned to another device on the network. Find the offending
device by checking the IP address of all devices on the network, then change
the address of one or the other devices - your PC or the other device on the
network with the same IP address, whichever would be easiest.

--
Richard G. Harper [MVP Desktop] (E-Mail Removed)
* NEW! Catch my blog ... http://msmvps.com/blogs/rgharper/
* PLEASE post all messages and replies in the newsgroups
* The Website - http://rgharper.mvps.org/


"Kent J" <(E-Mail Removed)> wrote in message
news:PVf1l.4797$(E-Mail Removed)...
> Hi all,
>
> I have a wireless network with a ADSL modem/router and a wireless DLink
> 'Range Extender'.
>
> When I run this I get: 'Windows - System Error. There is an IP-adressin
> conflict with another system on the network'.
> What does this mean? How can I fix it?
>
> Kent J.

OK!
I have a router with DHCP that provides PC:s running with a dynamic
IP-address and also a Dlink RangeExtender, with a static
IP-address,working as a slave.

If I check attached devices from my router I'll get:

# IP Address Device Name MAC Address
1 192.168.0.5 MYCOMPUTER 00:21:91A:78:51
2 192.168.0.31 DLINK 00:21:91A:78:51

Different IP-address but the same MAC Address.
Is that a problem?

Kent J.


Richard G. Harper [MVP] skrev:
> It means what it says - the IP address your computer is trying to use is
> already assigned to another device on the network. Find the offending
> device by checking the IP address of all devices on the network, then
> change the address of one or the other devices - your PC or the other
> device on the network with the same IP address, whichever would be easiest.
>

Yes its a problem


On 12/16/08 5:19 PM, in article sPV1l.4890$(E-Mail Removed), "Kent
J" <(E-Mail Removed)> wrote:

> OK!
> I have a router with DHCP that provides PC:s running with a dynamic
> IP-address and also a Dlink RangeExtender, with a static
> IP-address,working as a slave.
>
> If I check attached devices from my router I'll get:
>
> # IP Address Device Name MAC Address
> 1 192.168.0.5 MYCOMPUTER 00:21:91A:78:51
> 2 192.168.0.31 DLINK 00:21:91A:78:51
>
> Different IP-address but the same MAC Address.
> Is that a problem?
>
> Kent J.
>
>
> Richard G. Harper [MVP] skrev:
>> It means what it says - the IP address your computer is trying to use is
>> already assigned to another device on the network. Find the offending
>> device by checking the IP address of all devices on the network, then
>> change the address of one or the other devices - your PC or the other
>> device on the network with the same IP address, whichever would be easiest.
>>

What is a MAC-address anyway?
How can the address be the same?

Kent J.



Joel Guzman skrev:
> Yes its a problem
>
>
> On 12/16/08 5:19 PM, in article sPV1l.4890$(E-Mail Removed), "Kent
> J" <(E-Mail Removed)> wrote:
>
>> OK!
>> I have a router with DHCP that provides PC:s running with a dynamic
>> IP-address and also a Dlink RangeExtender, with a static
>> IP-address,working as a slave.
>>
>> If I check attached devices from my router I'll get:
>>
>> # IP Address Device Name MAC Address
>> 1 192.168.0.5 MYCOMPUTER 00:21:91A:78:51
>> 2 192.168.0.31 DLINK 00:21:91A:78:51
>>
>> Different IP-address but the same MAC Address.
>> Is that a problem?
>>
>> Kent J.
>>
>>
>> Richard G. Harper [MVP] skrev:
>>> It means what it says - the IP address your computer is trying to use is
>>> already assigned to another device on the network. Find the offending
>>> device by checking the IP address of all devices on the network, then
>>> change the address of one or the other devices - your PC or the other
>>> device on the network with the same IP address, whichever would be easiest.
>>>
>

See
http://www.google.com/search?hl=en&q...dress&aq=f&oq=
and
http://www.google.com/search?hl=en&q...dress+spoofing

Kent J wrote:
> What is a MAC-address anyway?
> How can the address be the same?
>
> Kent J.
>
>
>
> Joel Guzman skrev:
>
>> Yes its a problem
>>
>>
>> On 12/16/08 5:19 PM, in article sPV1l.4890$(E-Mail Removed),
>> "Kent
>> J" <(E-Mail Removed)> wrote:
>>
>>> OK!
>>> I have a router with DHCP that provides PC:s running with a dynamic
>>> IP-address and also a Dlink RangeExtender, with a static
>>> IP-address,working as a slave.
>>>
>>> If I check attached devices from my router I'll get:
>>>
>>> # IP Address Device Name MAC Address
>>> 1 192.168.0.5 MYCOMPUTER 00:21:91A:78:51
>>> 2 192.168.0.31 DLINK 00:21:91A:78:51
>>>
>>> Different IP-address but the same MAC Address.
>>> Is that a problem?
>>>
>>> Kent J.
>>>
>>>
>>> Richard G. Harper [MVP] skrev:
>>>
>>>> It means what it says - the IP address your computer is trying to
>>>> use is
>>>> already assigned to another device on the network. Find the offending
>>>> device by checking the IP address of all devices on the network, then
>>>> change the address of one or the other devices - your PC or the other
>>>> device on the network with the same IP address, whichever would be
>>>> easiest.
>>>>
>>

I'm afraid I still dont' get it.
I have three different MAC addresses that relates to MYCOMPUTER

1.) From ipconfig /all:
Physical address: 00-19-5b-eb-34-52

2.) From 'Configure' on the network card:
Local Administartion MAC Network Address: 00DEADBEEFCAFE

3.) From the router 'Attached Devices':
# IP Address Device Name MAC Address
1 192.168.0.4 MYCOMUTER 00:21:91A:78:51
2 192.168.0.31 RANGE EXTEND 00:21:91A:78:51

Should't it be just one MAC address per device?

Kent J.





Bob I skrev:
> See
> http://www.google.com/search?hl=en&q...dress&aq=f&oq=
> and
> http://www.google.com/search?hl=en&q...dress+spoofing
>
> Kent J wrote:
>> What is a MAC-address anyway?
>> How can the address be the same?
>>
>> Kent J.
>>
>>
>>
>> Joel Guzman skrev:
>>
>>> Yes its a problem
>>>
>>>
>>> On 12/16/08 5:19 PM, in article sPV1l.4890$(E-Mail Removed),
>>> "Kent
>>> J" <(E-Mail Removed)> wrote:
>>>
>>>> OK!
>>>> I have a router with DHCP that provides PC:s running with a dynamic
>>>> IP-address and also a Dlink RangeExtender, with a static
>>>> IP-address,working as a slave.
>>>>
>>>> If I check attached devices from my router I'll get:
>>>>
>>>> # IP Address Device Name MAC Address
>>>> 1 192.168.0.5 MYCOMPUTER 00:21:91A:78:51
>>>> 2 192.168.0.31 DLINK 00:21:91A:78:51
>>>>
>>>> Different IP-address but the same MAC Address.
>>>> Is that a problem?
>>>>
>>>> Kent J.
>>>>
>>>>
>>>> Richard G. Harper [MVP] skrev:
>>>>
>>>>> It means what it says - the IP address your computer is trying to
>>>>> use is
>>>>> already assigned to another device on the network. Find the offending
>>>>> device by checking the IP address of all devices on the network, then
>>>>> change the address of one or the other devices - your PC or the other
>>>>> device on the network with the same IP address, whichever would be
>>>>> easiest.
>>>>>
>>>
>

"Kent J" <(E-Mail Removed)> wrote in message
news:8UQ2l.4941$(E-Mail Removed)...
> I'm afraid I still dont' get it.
> I have three different MAC addresses that relates to MYCOMPUTER
>
> 1.) From ipconfig /all:
> Physical address: 00-19-5b-eb-34-52
>
> 2.) From 'Configure' on the network card:
> Local Administartion MAC Network Address: 00DEADBEEFCAFE
>
> 3.) From the router 'Attached Devices':
> # IP Address Device Name MAC Address
> 1 192.168.0.4 MYCOMUTER 00:21:91A:78:51
> 2 192.168.0.31 RANGE EXTEND 00:21:91A:78:51
>
> Should't it be just one MAC address per device?
>
> Kent J.
>
>
>
>
>
> Bob I skrev:
>> See
>> http://www.google.com/search?hl=en&q...dress&aq=f&oq=
>> and
>> http://www.google.com/search?hl=en&q...dress+spoofing
>>
>> Kent J wrote:
>>> What is a MAC-address anyway?
>>> How can the address be the same?
>>>
>>> Kent J.
>>>
>>>
>>>
>>> Joel Guzman skrev:
>>>
>>>> Yes its a problem
>>>>
>>>>
>>>> On 12/16/08 5:19 PM, in article sPV1l.4890$(E-Mail Removed),
>>>> "Kent
>>>> J" <(E-Mail Removed)> wrote:
>>>>
>>>>> OK!
>>>>> I have a router with DHCP that provides PC:s running with a dynamic
>>>>> IP-address and also a Dlink RangeExtender, with a static
>>>>> IP-address,working as a slave.
>>>>>
>>>>> If I check attached devices from my router I'll get:
>>>>>
>>>>> # IP Address Device Name MAC Address
>>>>> 1 192.168.0.5 MYCOMPUTER 00:21:91A:78:51
>>>>> 2 192.168.0.31 DLINK 00:21:91A:78:51
>>>>>
>>>>> Different IP-address but the same MAC Address.
>>>>> Is that a problem?
>>>>>
>>>>> Kent J.
>>>>>
>>>>>
>>>>> Richard G. Harper [MVP] skrev:
>>>>>
>>>>>> It means what it says - the IP address your computer is trying to use
>>>>>> is
>>>>>> already assigned to another device on the network. Find the
>>>>>> offending
>>>>>> device by checking the IP address of all devices on the network, then
>>>>>> change the address of one or the other devices - your PC or the other
>>>>>> device on the network with the same IP address, whichever would be
>>>>>> easiest.
>>>>>>
>>>>
>>

Get rid of the Locally Administered MAC Address, change the setting in
Configure to "Not Present".

Shutdown all your PCs and routers. Wait 30 seconds, Power up your router(s)
and wait for them to settle, power up your PCs and check for problems.

Tim Jackson skrev:
> "Kent J" <(E-Mail Removed)> wrote in message
> news:8UQ2l.4941$(E-Mail Removed)...
>> I'm afraid I still dont' get it.
>> I have three different MAC addresses that relates to MYCOMPUTER
>>
>> 1.) From ipconfig /all:
>> Physical address: 00-19-5b-eb-34-52
>>
>> 2.) From 'Configure' on the network card:
>> Local Administartion MAC Network Address: 00DEADBEEFCAFE
>>
>> 3.) From the router 'Attached Devices':
>> # IP Address Device Name MAC Address
>> 1 192.168.0.4 MYCOMUTER 00:21:91A:78:51
>> 2 192.168.0.31 RANGE EXTEND 00:21:91A:78:51
>>
>> Should't it be just one MAC address per device?
>>
>> Kent J.
>>
>>
>>
>>
>>
>> Bob I skrev:
>>> See
>>> http://www.google.com/search?hl=en&q...dress&aq=f&oq=
>>> and
>>> http://www.google.com/search?hl=en&q...dress+spoofing
>>>
>>> Kent J wrote:
>>>> What is a MAC-address anyway?
>>>> How can the address be the same?
>>>>
>>>> Kent J.
>>>>
>>>>
>>>>
>>>> Joel Guzman skrev:
>>>>
>>>>> Yes its a problem
>>>>>
>>>>>
>>>>> On 12/16/08 5:19 PM, in article sPV1l.4890$(E-Mail Removed),
>>>>> "Kent
>>>>> J" <(E-Mail Removed)> wrote:
>>>>>
>>>>>> OK!
>>>>>> I have a router with DHCP that provides PC:s running with a dynamic
>>>>>> IP-address and also a Dlink RangeExtender, with a static
>>>>>> IP-address,working as a slave.
>>>>>>
>>>>>> If I check attached devices from my router I'll get:
>>>>>>
>>>>>> # IP Address Device Name MAC Address
>>>>>> 1 192.168.0.5 MYCOMPUTER 00:21:91A:78:51
>>>>>> 2 192.168.0.31 DLINK 00:21:91A:78:51
>>>>>>
>>>>>> Different IP-address but the same MAC Address.
>>>>>> Is that a problem?
>>>>>>
>>>>>> Kent J.
>>>>>>
>>>>>>
>>>>>> Richard G. Harper [MVP] skrev:
>>>>>>
>>>>>>> It means what it says - the IP address your computer is trying to use
>>>>>>> is
>>>>>>> already assigned to another device on the network. Find the
>>>>>>> offending
>>>>>>> device by checking the IP address of all devices on the network, then
>>>>>>> change the address of one or the other devices - your PC or the other
>>>>>>> device on the network with the same IP address, whichever would be
>>>>>>> easiest.
>>>>>>>
>
> Get rid of the Locally Administered MAC Address, change the setting in
> Configure to "Not Present".
>
> Shutdown all your PCs and routers. Wait 30 seconds, Power up your router(s)
> and wait for them to settle, power up your PCs and check for problems.
>
>
>
Thanks!
Now it seems to work. I have different MAC-adresses.

3 192.168.0.4 MYCOMPUTER 00:19:5B:EB:34:52
4 192.168.0.31 RANGE EXTEND 00:21:91A:78:51


Kent J.

"Kent J" <(E-Mail Removed)> wrote in message
news:Ja94l.5048$(E-Mail Removed)...
> Tim Jackson skrev:
>> "Kent J" <(E-Mail Removed)> wrote in message
>> news:8UQ2l.4941$(E-Mail Removed)...
>>> I'm afraid I still dont' get it.
>>> I have three different MAC addresses that relates to MYCOMPUTER
>>>
>>> 1.) From ipconfig /all:
>>> Physical address: 00-19-5b-eb-34-52
>>>
>>> 2.) From 'Configure' on the network card:
>>> Local Administartion MAC Network Address: 00DEADBEEFCAFE
>>>
>>> 3.) From the router 'Attached Devices':
>>> # IP Address Device Name MAC Address
>>> 1 192.168.0.4 MYCOMUTER 00:21:91A:78:51
>>> 2 192.168.0.31 RANGE EXTEND 00:21:91A:78:51
>>>
>>> Should't it be just one MAC address per device?
>>>
>>> Kent J.
>>>
>>>
>>>
>>>
>>>
>>> Bob I skrev:
>>>> See
>>>> http://www.google.com/search?hl=en&q...dress&aq=f&oq=
>>>> and
>>>> http://www.google.com/search?hl=en&q...dress+spoofing
>>>>
>>>> Kent J wrote:
>>>>> What is a MAC-address anyway?
>>>>> How can the address be the same?
>>>>>
>>>>> Kent J.
>>>>>
>>>>>
>>>>>
>>>>> Joel Guzman skrev:
>>>>>
>>>>>> Yes its a problem
>>>>>>
>>>>>>
>>>>>> On 12/16/08 5:19 PM, in article sPV1l.4890$(E-Mail Removed),
>>>>>> "Kent
>>>>>> J" <(E-Mail Removed)> wrote:
>>>>>>
>>>>>>> OK!
>>>>>>> I have a router with DHCP that provides PC:s running with a dynamic
>>>>>>> IP-address and also a Dlink RangeExtender, with a static
>>>>>>> IP-address,working as a slave.
>>>>>>>
>>>>>>> If I check attached devices from my router I'll get:
>>>>>>>
>>>>>>> # IP Address Device Name MAC Address
>>>>>>> 1 192.168.0.5 MYCOMPUTER 00:21:91A:78:51
>>>>>>> 2 192.168.0.31 DLINK 00:21:91A:78:51
>>>>>>>
>>>>>>> Different IP-address but the same MAC Address.
>>>>>>> Is that a problem?
>>>>>>>
>>>>>>> Kent J.
>>>>>>>
>>>>>>>
>>>>>>> Richard G. Harper [MVP] skrev:
>>>>>>>
>>>>>>>> It means what it says - the IP address your computer is trying to
>>>>>>>> use is
>>>>>>>> already assigned to another device on the network. Find the
>>>>>>>> offending
>>>>>>>> device by checking the IP address of all devices on the network,
>>>>>>>> then
>>>>>>>> change the address of one or the other devices - your PC or the
>>>>>>>> other
>>>>>>>> device on the network with the same IP address, whichever would be
>>>>>>>> easiest.
>>>>>>>>
>>
>> Get rid of the Locally Administered MAC Address, change the setting in
>> Configure to "Not Present".
>>
>> Shutdown all your PCs and routers. Wait 30 seconds, Power up your
>> router(s) and wait for them to settle, power up your PCs and check for
>> problems.
>>
>>
>>
> Thanks!
> Now it seems to work. I have different MAC-adresses.
>
> 3 192.168.0.4 MYCOMPUTER 00:19:5B:EB:34:52
> 4 192.168.0.31 RANGE EXTEND 00:21:91A:78:51
>
>
> Kent J.
>

YW