When installing a certificate using Microsoft IIS 7.0, you may receive one of the following error messages:
Note: The certificate may already be installed regardless of the error message.
This issue occurs because IIS Manager performs a lookup operation to look for a friendly name of the certificate during the installation. However, the code that performs this lookup operation misses this specific case, and it does not know how to retrieve the friendly name of a certificate in a PKCS#7 file. Therefore, the lookup operation fails, and you receive the error message.
This is a known issue with IIS 7.0. Please see the following Microsoft Knowledge Base Article regarding this issue:
To resolve this problem, check if the certificate is installed by performing the following steps:
Step 1: Create a 'Certificates' snap-in within the MMC
Step 2: Locate the SSL certificate
Step 3: Bind the SSL certificate to the web site in IIS
Step 4: Verify certificate installation