John Wunderlich said:
In Event Viewer I see many errors like this
---------
DHCP
"The IP address lease 192.168.x.xx for the Network Card with
network address xxxxxxxxxx has been denied by the DHCP server
192.168.1.1 (The DHCP Server sent a DHCPNACK message)." [I've
inserted the x's for security.]
Is this a laptop that often moves from one network to another?
When contacting a DHCP server for an IP address, the computer
usually expresses a preference for the last IP address that it
had. If the DHCP server determines that that IP address is
currently unavailable or that the requested address does not
belong to the subnet served by the DHCP server, then you will log
the error that you cite in the Event Viewer. This is perfectly
normal and simply indicates that the "quick" DHCP assignment
failed and that the regular DHCP assignment process is being
forced.
HTH,
John
Thanks John. This is just a WinXP desktop PC, and I'm the sole
user. The only 'network' is my BT Broadband connection and a cable
connecting my old PC to my router temporarily, to allow copying of
files. What and where is 'the DHCP server' that makes these
choices please?
Must say I do find this stuff very hard going! But if I've got the
drift of what you're saying, then it sounds like I don't need to
worry? Some 'lease' or other is not about to come to a sudden
halt, excommunicating me (literally) from the Net?
The DHCP Server is the program that assigns you your IP address when
you connect to the network. If you connect directly to your
Broadband connection, the DHCP server is managed by your ISP. If you
connect to a router, then the router provides the DHCP function.
Connecting to a router, you usually get an IP address like
192.168.x.x. Connecting to your broadband, you would get a different
IP address. When your computer asks the DHCP server for an IP
address, it usually tries to take a shortcut by saying something like
"I need an IP address and, by the way, I'd prefer the last IP address
I had which was X.X.X.X" It would not be unusual for the DHCP server
to reply saying "I'm sorry but X.X.X.X is not currently available".
When this happens, you get the message that you see in your Event Log
and your computer will ask again for an IP address but this time it
will not express a preference.
When assigned an IP address via DHCP, there will be a time limit on
the use of this IP address. This is the "lease" time. Routers will
usually default to about a week, and ISPs will default anywhere
between a couple of hours to a couple of days. You can see your
lease expiration by bringing up a command window (start->run->cmd)
and entering the command: ipconfig /all
When the lease is half-over, your computer will automatically attempt
to renew the lease. It is rare for a lease not to renew; however,
should it not renew before it expires, yes you will be (as you put
it) excommunicated from the network. The main reason for the lease
is that should you drop off the network without formally releasing an
IP address, that IP address will eventually automatically expire and
revert back into the pool for assignment to another user.
HTH,
John