Browsers and the CLI client trust the Signotaur server only if its HTTPS certificate chains to a trust anchor they already recognise. A self-signed certificate, or a certificate from a private CA (Signotaur's Internal CA or ADCS) whose root is not in the client's trust store, is not recognised — so browsers show a "Your connection is not private" warning and the CLI reports certificate errors. To remove these warnings, install the trust anchor in each client's trusted root store.
If the server uses Signotaur's Internal CA or ADCS for its web certificate, the Web Certificate → Trust Distribution tab in the admin UI provides the Root CA download and the same installation steps in-product. Trusting the Root once covers every future renewal — intermediate rotations and certificate renewals still chain to the same Root.
The certificate you need to install on clients depends on how the server's web certificate is issued:
.crt, Base64 text) or Download DER (.cer, binary).Once you have the certificate file, install it into the trusted root store on each client using the appropriate method for the platform.
Distributes the certificate to every domain-joined machine.
root-ca.crt or .cer) to disk.Default Domain Policy).gpupdate /force on a target machine to test.Installs the certificate on a single machine.
root-ca.crt to disk and double-click it.Save root-ca.crt to disk, then add it to the system trust store.
Debian / Ubuntu:
sudo cp root-ca.crt /usr/local/share/ca-certificates/signotaur-root.crt
sudo update-ca-certificates
RHEL / Rocky / Fedora:
sudo cp root-ca.crt /etc/pki/ca-trust/source/anchors/signotaur-root.crt
sudo update-ca-trust
root-ca.crt — Keychain Access opens.Firefox uses its own trust store on most platforms (not the OS one).
root-ca.crt to disk.about:preferences#privacy.root-ca.crt.Enable security.enterprise_roots.enabled in about:config to make Firefox honour the OS trust store instead.
SignotaurTool uses the system trust store on whatever OS it runs on. Once the certificate is installed via one of the methods above, the CLI will trust the server with no further action.
Fully close and reopen the browser (not just a tab reload) so it picks up the new trusted root. If a page was already loaded over the untrusted certificate, the browser may keep showing a warning for the rest of the session — open the site in a fresh window (or an incognito/InPrivate window) to confirm trust is working.
Chrome sometimes caches the old certificate, so the warning may persist even after the certificate is trusted. Press Ctrl + Shift + Delete, set the time range to All time, check Cached images and files, click Delete data, then restart Chrome.