Authentication mode changing(?)

I have an AD integrated domain running on a single server so far (Win2K-sp3 and Exch2K-sp2). I want to configure my exchange virtual directories so that I am using basic authentication with SSL for OWA. The default security settings for the directories were ‘Windows integrated Authentication’. When I change the settings to the way I want them, everything works properly, but if I reboot the machine the authentication mode changes back to ‘Windows integrated’. I’m working with OWA within the default site and the authentication for the default site is ‘basic mode’ and those settings are staying that way. Any ideas why my settings are changing by themselves?