Syncthing not installing on a debian NAS

[calmh (Jakob Borg)]

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Can't update syncthing via apt anymore

Hi, since today I have an error during “apt update” on an ubuntu 20.04 system. I saw some new instructions on apt.syncthing.net and followed them. However, this error remains: Fehl:15 https://apt.syncthing.net syncthing Release Certificate verification failed: The certificate is NOT trusted. The certificate chain uses expired certificate. Could not handshake: I got the newest gpg file, just moments ago, so I guess the file is out-of-date…