You have a private key that corresponds to this certificate but CryptAcQuireCertificatePrivateKey failed
First download “SSL Diagnostics Version 1.1 (x86)” and find out why your SSL does not work… (link below)
If first solution does not work, try below:
1. Set the correct permission for Machinekey folder C:\Documents and Settings\All Users\Application Data\Microsoft\Crypto\RSA\MachineKeys
2. Add administrator and system Full Control Permissions.
3. Restart IIS