A-unknown-CA">&quot;CA&quot;/&quot;unknown CA&quot;</dt>
<dd>

<p>A valid certificate chain or partial chain was received, but the certificate was not accepted because the CA certificate could not be located or couldn&#39;t be matched with a known, trusted CA. This message is always fatal.</p>

</dd>
<dt id="AD-access-denied">&quot;AD&quot;/&quot;access denied&quot;</dt>
<dd>

<p>A valid certificate was received, but when access control was applied, the sender decided not to proceed with negotiation. This m