Hi Dave, thanks for your question.

One thing I’ve noticed about IE over the years is that it’s quite clingy with its cache. It may be that the older certificate is cached (although this would be somewhat irregular as SSL content shouldn’t really be cached).

Depending on how you installed the certificate, the CSR, Private Key, Certificate and CA certificate info should be all available under the certificate you uploaded into Domains > domain.com > SSL Certificates.

Try this: In Plesk’s main menu, go to Settings > SSL Certificates and add the new certificate info there. Set it as the default and, optionally, hit the Secure Panel link, to set it up as the panel’s certificate.

The next step is to change which certificate was used by default on the IP address, so change this in the drop down in Settings > IP Addresses >

Finally, to check that the certificate is set as the site’s default, visit Domains > domain.com > Web Hosting Settings.

Hope this helps!