Hi raik,
you have to add the certificate of your (active directory integrated) Certificate Authority to the zammad certificate store (settings->security->ssl certificates)
i guess your domain controller uses a certificate from your internal ca. so you have to add the certificate of your ca to zammad. So zammad could verify the certificate of the active directory-server (DC).
The error: “certificate verify failed (unable to get local issuer certificate)” not a connect problem, but a unknown trust state.
