Sorry - I thought there would be more output. Probably I misremembered from tests using OpenSSL on the command line, which is a bit cumbersome with Windows (but works fine with Cygwin).

So there are two more suggestions:

• Fire your certificate against an online test service, for example https://certauth.idrix.fr/, by just changing the endpoint URL in your code. This service requires client certificates and responds by providing a technical description of the certificate you provided.
• Import the client certificate and the corresponding CA certificate into a browser and then read the page.

Maybe one of those gives more insight?