Note: Depending on your security settings with Windows 7, you may be prompted when attempting to open the certificate. This dialogue box may say, A website wants to open web content using this program on your computer. The name of the Program should say Crypto Shell Extensions and the publisher should say, Microsoft Windows. If this is correct, then click on the Allow button to continue.
When the Certificate Import Wizard starts, you will see the Welcome Screen (seen below). At this screen, you can click on the Next button.
Include all extended properties - Should be checked.
After you have selected your options and you have entered in the password, click on the Next button.
You will then receive a small window that confirms the installation of the certificate. When you are finished, click on the OK button.