Error: "Class not registered" when provisioning a certificate to an IIS7x server

Symptom:

When pushing a certificate to an IIS 7x server, the following error is displayed:

Install Certificate failed with error: Retrieving the COM class factory....failed due to the following error: 80040154 Class not registered...

Cause:

 The IIS6 Compatability Components need to be installed on:

1. The Microsoft CA server 
2. The server that we are trying to push the certificate to.
3. The director sever.

Resolution:

Install the IIS6 Compatability Components and retry the certificate push.

Detailed steps are available here