Installing GeoTrust SSL Digital Certificate comes with error.

I just renewed the SSL digital certificate of one of our web server for another one year. I'm installing and renewing SSL digital certificate for many years but this time I encounter a digital error. So I tried to troubleshoot to learn what's going on, and provide solution to fix this problem.

The renewal of digital certificate is the same process. You go to the server to create a new digital certificate, buy a SSL digital certificate from the vendor e.g. Verisign, GeoTrust, RapidSSL, and other provider, and then submit it. I choosed GeoTrust because it is very reasonable price to maintain a secure tunnel from your client internet browser to the web server.

The process is completed, the web server digital certificate is valid for another year. But I have some users complaining about "The security certificate presented by this website was not issued by a trusted certificate authority." I find out this from my Windows Vista users. I know I can ask them to check with other computer using Windows XP or Windows 7, this will work.

But I have the same users in the past so I digged more to get additional information.

I used the SSL Checker to verify the old and new digital certificates. The two web servers are using GeoTrust certificate, one certificate is not trusted in all web browsers (see the captured image above) and one is correctly listed (see the captured image on the right) in the certificate authority. I also noticed the Issuer changed from Equifax to GeoTrust DV SSL CA.

There are two solutions to resolve this certificate error. The first one is easy, let them use other computer using Windows XP or Windows 7 with IE 7.0 or latest. The second option is to follow the recommendation provided by SSL Shopper.

References:
SSL Checker. Retrieved last Sept. 8, 2010 from http://www.sslshopper.com/ssl-checker.html
SSL Certificate Not Trusted Error. Retrieved last Sept. 8, 2010 from http://www.sslshopper.com/ssl-certificate-not-trusted-error.html