Where is the SSL-certificate used by WebAccess for an https-connection?

Which SSL-certificate is used by WebAccess to establish an https-connection? Where in the file system is it located?

The currently used certificate is not accepted by FireFox (“SEC_ERROR_REUSED_ISSUER_AND_SERIAL”) and no exception can be set.

CloudBerry 4.1.5.822 WebAccess.

Thanks!

Hello? Anybody? Julia?