Let's Encrypt and other issues with poste.io docker image installed over Caprover

[AMDG per Mariam]

Hello all. I have installed poste.io (tried several versions including the latest 2.2.30) docker using Caprover. poste.io is behind a nginx proxy. Lets encrypt is managed by Caprover. I am having several errors, visualized by the diagnostic page(see attached screenshot below). To resolve the “Let’s encrypt token exchange test - Connection refused” error, I tried to mapping the following files to poste.io:

/captain/data/letencrypt/etc/live/mail.domain.de/chain.pem -> /data/ssl/ca.crt
/captain/data/letencrypt/etc/live/mail.domain.de/cert.pem -> /data/ssl/server.crt
/captain/data/letencrypt/etc/live/mail.domain.de/privkey.pem -> /data/ssl/server.key

(ref: https://github.com/caprover/one-click-apps/issues/80#issuecomment-590934294)

How can I resolve these errors, at least the Let’s encrypt error? Any help will be appreciated.

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