Some servers are shipped with Thawte's old Server CA root. The solution is to update the Thawte CA root in the server. You need to check your server configuration and make sure that the server is 'listening' on the default secure port, 443. You could also be connecting to a server that is not running. The solution for this is to enable SSL3 in your webserver.
Every certificate contains a domain name.
There is a bug in some versions of IE 4 for the Mac platform, which causes it to produce this error message even if the certificate name matches the domain name perfectly. This is a bug, and we cannot affect it one way or another. This problem occurs when a server sends an expired certificate as well as its own certificate to the browser. This problem does not occur with versions 4.5.1 and 5.0. Root Certificates Root certificates contain the public keys that correspond to the private keys we use to sign certificates.