extensions error - kills server

When I try to enable any extensions, it kills the server, making it impossible to view any website. I've tried multiple versions of PHP with multiple php.ini files. I've made sure the extension_dir was pointing to the correct extension directory, and that the extensions I tried to enable did in fact exist. Still nothing. In order for my websites to work at all, I cannot have extensions enabled. Has anyone encountered this before? If so, is there a solution (aside from moving to a linux box). Any help is graciously appreciated. Adam Jackett Allaboutwebsites.com Inc.