ok. i found this solution, but this not works for me.
https://forum.proxmox.com/threads/the-server-certificate-etc-pve-local-pve-ssl-pem-is-not-yet-active.26459/
in /var/log/daemon.log:
Jun 14 15:39:41 proxmox pvedaemon[18182]: ipcc_send_rec failed: Transport endpoint is not connected
Jun 14 15:39:41 proxmox pvedaemon[18182]: authentication failure; rhost=::ffff:31.17.187.39 user=root@pam msg=RSA.xs:178: OpenSSL error: no start line at...