Occasionally a certificate will become corrupt or is installed without a properly generated private key. Such is the case with a bare CER certificate file. When this happens it will often no longer function with Exchange, IIS, or other web servers.
Here is how to recreate the private key for an installed certificate.
- Open the Certificates management console (Start > Run > MMC > Add/Remove Snap-in > Certificates > Computer Account > Local Computer)
- Expand Certificates (Local Computer) > Personal > Certificates
- View the properties of the certificate you want to create a private key for. On the Details tab, click Serial number.