hi Anton,
To fix this error the certificate needs to be regenerated, from the saml settings click the 'Regenerate certificate' button, or go here:
http://moodle.example/auth/saml2/regenerate.php
and resave the certificate. You will need to re-import the SP metadata again with your IdP.
> Now we changed to OpenID connect-authentication, also because of SAML didn't provide user-sync via cron job.
Syncing via cron doesn't make any sense for either SAML as it is only authentication protocol, but auth_saml2 is designed to sit on top of any other auth plugin, eg you can sync and provision identities via auth_ldap sync and then SSO authenticate via saml.
To fix this error the certificate needs to be regenerated, from the saml settings click the 'Regenerate certificate' button, or go here:
http://moodle.example/auth/saml2/regenerate.php
and resave the certificate. You will need to re-import the SP metadata again with your IdP.
> Now we changed to OpenID connect-authentication, also because of SAML didn't provide user-sync via cron job.
Syncing via cron doesn't make any sense for either SAML as it is only authentication protocol, but auth_saml2 is designed to sit on top of any other auth plugin, eg you can sync and provision identities via auth_ldap sync and then SSO authenticate via saml.