DNS Problem

If I have understood you right. These laptops are used for work and home but you need to change the settings for when they are at home right? Well have you tried creating a new hardware Profile? This is located under My Computer Properties, Hardware. Create a new Profile with the users home Network settings.

Hi,
Just to Clarify - If your laptop users are receiving the dns servers settings from DHCP then they are not static. When the laptop boots up next time it should try and get new settings from dhcp, and only retain old settings if it unable to get a new dhcp address and is able to ping the gateway given out by the your works dhcp server (think about it - if a laptop comes online and can't get a new dhcp lease then it needs to know whether or not to use the last address it had, but that addy will only be relevant if it is still on the same network it was on when it had that last address, so to test this it pings the last gateway it knew about and - if it gets a reply - takes that as proof it is still on the same network and uses the old address). If your users are plugging in at home but still using the dns servers assigned by your dhcp at work then my first guess would be that the dns servers aren't being assigned by dhcp at all but have been added to each laptop.

Or are you saying that the laptops are picking up the dns servers of their isp, but are incorrectly resolving names as if they were using works dns servers. In this case I would check the hosts and lmhosts files for static entries.

Other than that i think you need to explain a bit more...

ain't laptops a pita to support on a network. i am always peeling off the password post it on the dang things...
anyhow, i believe the users will have to do a fiddle to move and forth. here is the fiddle i think they need (snipped from http://support.microsoft.com/default.aspx?scid=kb;en-us;314095#XSLTH3152121123120121120120
How to troubleshoot possible causes of Internet connection problems in Windows XP

Turn on the option to use a default gateway on the remote network
If you connect to a local network by using a network adapter and, at the same time, connect to your ISP by using a modem, configure your dial-up connection so that any routing conflicts are resolved in favor of your dial-up connection to your ISP. Follow these steps: 1. In Control Panel, double-click Network Connections.
2. Right-click your Internet connection, click Properties, and then click the Networking tab.
3. Click the Internet Protocol adapter, click Properties, and then click Advanced.
4. Click to select the Use default gateway on remote network check box, and then click OK.
5. Click OK.

humm you do this with hardware profiles, different user accounts and/or allowing users local machine log in rights.

here's a link for setting up hardware profiles in XP for laptops. http://support.microsoft.com/default.aspx?scid=kb;en-us;308577

If they have DHCP addresses for work, then there should be no problem. If they get DHCP addresses, but Static DNS, then the issue should be resolved by setting up the DHCP server to give out the DNS addresses, and setting the clients to get DNS from DHCP.
Otherwise, this sounds like a local problem. Does their ISP connect their computers with DHCP or static IP's? If static, create a "alternate Configuration".
Are these users using a router? If so the router should be configured for DHCP and set it up to connect to the ISP.
Otherwise, it may be a problem on the ISP side, including bad cable/dsl modem.

IP Addressing issues like this at my place were solved by telling the user to ensure they SHUT DOWN the computer when at work before leaving--not just Hybernate or Sleep.

We had a similar problem to this where the user could access the internet at work but not from their home dial-up account.

A check of the internet settings showed the proxy to be the work proxy, which did not allow them to use the home dial-up connection.

Changing this option fixed the problem.