Working through an issue with Exchange 2013 and the looping ECP/OWA. Appears to be a results of the certificate not being imported properly. After exporting with the private and attempting to import with:
certutil -csp "Microsoft RSA SChannel Cryptographic Provider" -importpfx <path_to_cert>
Results in an error:
CertUtil: -importPFX command FAILED: 0x80090029 (-2146893783)
CertUtil: The requested operation is not supported.