IP address conflict

[Guest]

Hi

My SO's computer is running XP Home and regularly gets an error message
indicating an IP address conflict when my test machine is up. All addresses
have been manually assigned and there is no apparent conflict. Addresses are
192.168.1.x, x = 1(modem),2(SO),13(me), and 100(test). Is corruption a
possibility? She was having intermittent crashes until I ran sfc -purgecache.

TIA
Jim

 

[D.Currie]

Hi

My SO's computer is running XP Home and regularly gets an error message
indicating an IP address conflict when my test machine is up. All
addresses
have been manually assigned and there is no apparent conflict. Addresses
are
192.168.1.x, x = 1(modem),2(SO),13(me), and 100(test). Is corruption a
possibility? She was having intermittent crashes until I ran
sfc -purgecache.

TIA
Jim

I'd say just change the ip on either that computer or your test machine and
see what happens. You've only got 4 computers and a lot of numbers to choose
from. Some things just aren't worth spending a lot of time troubleshooting,
and this seems like one of them, unless you've got some particular
attachment to that set of numbers.

 

[Steve N.]

Hi

My SO's computer is running XP Home and regularly gets an error message
indicating an IP address conflict when my test machine is up. All addresses
have been manually assigned and there is no apparent conflict. Addresses are
192.168.1.x, x = 1(modem),2(SO),13(me), and 100(test). Is corruption a
possibility? She was having intermittent crashes until I ran sfc -purgecache.

TIA
Jim

Have you tried setting it to automatically obtain IP address?

Steve

 

[Guest]

I tried that, but nothing happens. No error reported, no address assigned.

Jim

 

[R. McCarty]

Windows remembers every Local Area Connection ever established
on your PC. It could be that a inactive NIC/LAC is the root cause of
the conflict.
Check Device Manager (Click Show Hidden Devices) Network
and see if you have numbered, multiple instances of the same NIC.
Also, check Network Connections and see what LAC is present. If
it's numbered then you have multiple LAC's stored in the Registry.

 

[Randy Harris]

What exactly is it that you have at 192.168.1.1? Modems don't have IP
addresses. Perhaps a DSL router or something like that? If so, is it DHCP
server enabled? If so, configure it so that it passes out addresses above
your highest static address. You have a system statically assigned .100,
change the DHCP server to assign .129 and above.

 

[Steve N.]

I tried that, but nothing happens. No error reported, no address assigned.

Jim

I am presuming you are using ICS/IPM (Internet Connection Sharing in
Windows world/IP Masquerading in *nix world).

I suspect this is because you are using a non-standard IP range on the
host machine and the client can't find it with either DHCP (Automatic)
or static IP settings.

Although it is possible to use ICS with static IP addresses Windows
doesn't like it and I've had best results using the defaults. In
addition you are using an IP range that is non-standard for ICS/IPM. The
host standard IP configuration is 192.168.0.1, not 192.168.1.1.

I've also found in changing IP configurations that Windows keeps old
values in the registry for default gateway and DNS on the client
machines based not only on IP address but machinename/hostname, that can
cause problems if the real gateway address or machinename has changed.
I've had to search the registry for Default gateway entries and delete
them. Also if you are using an ethernet switch or "smart hub" that
builds an internal address table it may need to be power-cycled after
configuration changes are made in order to re-build its table.

So, if I were you I would approach it like this:
Set the host machine up with default settings for ICS on the dialup
connection which will make all the necessary IP settings for you on its
NIC, set the client machines to obtain IP address automatically, search
the registry for Default Gateway entries on all client machines and
delete them if they are incorrect, shut everything down except the ICS
host and modem, bring up the network device (hub, switch), then power up
the Client machines. It may also take several restarts of the clients to
get the addresses stablized.

Steve