when i try to change the way users log on. I get a client servises for netware must be uninstalled

This Microsoft Knowledge Base article has the answer: Error Message When You Try to Turn On Welcome Screen or Fast User SwitchingBoulder Computer MavenMicrosoft Most Valuable Professional

if you can't find Client service for netware on your computer to uninstall, and you want your welcome screen back on try this, go to control panel, click internet conection, when box opens right click internet conection, then click properties, a box should open with the words on it ( this conection uses the following items ) you wont see client service for netware, but at the bottom of the box you will see ( install )( uninstall ). click the install button, it will now open a new box and you should see client service for netware and possibly client for microsoft. highlight client service for netware and then click install, your computer should now install it, reboot your computer, then go to control panel, click internet conection, right click internet conection, click properties, the same box should reopen but now you should see in the box client service for netware, what you now do is hightlight it and click uninstall, your computer should now uninstall it, reboot computer, go to control panel click users, then click change the users log on, you should now see your welcome screen back on,