Backup | Avoid database corruption | Restore tests suggestions | Backup encryption

I have tried to backup the entire bwdata folder with cobian. It works ok, but it does not copy the 4 .pem files which are stored in the letsencrypt\live\bitwarden.mydomain.com\ folder, that is:

  1. cert.pem
  2. chain.pem
  3. fullchain.pem
  4. privkey.pem

Cobian log tells me that the reason is: The file cannot be accessed by the system

What options do I have to solve that?

Thank you all.

Andrea