Forcing redirection from http to https

Hello,

We have a customer that had us install a SSL certificate on their site. They want the user to be automatically redirected from http://domain.com or http://www.domain.com to https://www.domain.com . They are on a shared windows plan.
Any ideas would be appreciated.

We can do a require https setting on windows, but then if you visit non https it gives an error message, so in such cases I recommend a code based redirection to the ssl channel, because simply put any error means a vast majority of people simply hit the back button.