Microsoft® Exchange Server 2007 Administrator's Companion

Securing Messaging in Outlook 2007

From the client perspective, one question that must be answered is how the Outlook 2007 client knows which certificates to trust. The answer is found in the properties of Microsoft Internet Explorer. When Internet Explorer is installed, a large number of root certificates are embedded in the installation. Outlook uses the Internet Explorer cryptographic service provider to read these certificates and then determine whether the CA is trusted. To see which CAs are trusted, in Internet Explorer, choose Internet Options from the Tools menu and then display the Content tab and click Certificates. In the Certificates window, click the Trusted Root Certification Authorities tab. Figure 21-24 shows a partial list of ...