Heads up for SBS Sites using self-signed certificates
SBS (Small Business Server) uses self-signed certificates by default. This may cause an issue for your users if they are running Internet Explorer 7. As you can see from the screenshot, direct navigation to the Outlook Web Access log-on URL is blocked by IE7 when self signed certificates are used.
To help avoid confusion I'd recommend you alert your users to this change in behaviour sooner rather than later, so that they understand that there is nothing wrong with your site or their computer.
Here are the hoops your user will have to jump through to stop the warning page from appearing every time they go to your site.
First, they will see this page.
Your users need to click on Continue to this website (not recommended)
They will be presented with the red Address Bar and certificate warning:
Click on the Certificate Error button to open the information window.
Click on View Certificates. Then click on Install Certificate.
You'll see yet another warning.
Click on Yes, then you're done.
IE7 on Windows Vista
We see the same problem with self-signed certificates when using IE7 on Windows Vista, but the option to install certificates will not be available unless you run IE with administrator rights (right click the IE icon, select "Run as Administrator").