This parse error is displayed if the VPN concentrator does not have a root Certificate Authority (CA) certificate installed.
Regardless of whether Simple Certificate Enrollment Protocol (SCEP) or manual enrollment is used, the VPN concentrator must have a root CA installed if third-party certificates are used. In order to obtain and install the Secure Socket Layer (SSL) certificates, perform this procedure:
Obtain and install the root CA certificate.
Create an enrollment request for one or more identity certificates.
Request an identity certificate from the same CA that issued the root CA certificate.
Install the identity certificate on the VPN concentrator.
Enable Certificate Revocation List (CRL) checking and caching.
Ideally, this procedure resolves the issue. Refer to Certificate Management for additional help on certificate enrollment.