Import a Trusted Root Certification Authority In Windows 7/Vista/XP.

1. Start Microsoft Management Console (MMC) Tool

Click Start -> Run -> Enter 'MMC' and click 'OK'

 2. Click File -> Add/Remove Snap-In...

3. Add Certificate.

Select 'Certificates' in left panel and click 'Add' to move to right panel , Then Click 'OK'

4. Select 'Computer Account' option and click 'Next'