PCAW encryption - unknown CA

I’m trying to use PCAnywhere 11.5 with public key encryption.

I get this error:

Host is denying connection because Remote cannot connect at level: Public Key.
Could not find the certificate of the certificate authority that issued Remote’s certificate.
Cannot find object or property.

The CA is Quo Vadis. The certificate is recognized as valid by Windows on both the host and remote.

I used CERTMGR to export the certificate to a PKCS#7 (P7B) file and selected the “include all certificates in the certification path if possible” option. The “encryption” tab in PCAW preferences on both host and remote point to copies of the P7B file

Any ideas?

TIA
David