SSL (and dependent services) problem

I have a SBS SP1 system and all fo the sudden SSL and depedent
services (like Outlook over HTTPS) is failing requiring reboot to work
correctly. For example, ordinarily if I went to http://www.domain.com/exchange
from outside the network the server would automatically redirect to
https://www.domain.com/exchange (secure) and I could log in. However,
the redirect now does not work. If I go to http://www. (since
required SSL is checked for OWA) it get an http page cannot be
displayed error. Similarly, outlook over HTTPS fails. I have tried
simply restarting HTTPS (and WWW) as well as whole IIS stack but only
reboot solved problem. This is the second time this has happend in as
many days. I have reviewed logs and see no errors (at all really) and
certainly nothing that would cause this problem.

Any thoughts are appreciated.

-Eric