[PLUG] Issue in Debian 8.11 while installing letsencrypt using apt-get

[Amey Abhyankar]

Hello,

I am facing issue while installing letsencrypt in Debian 8.11

Command = sudo apt-get install letsencrypt
Sample error =
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Err http://ftp.debian.org/debian/ jessie-backports/main
python-cffi-backend amd64 1.9.1-2~bpo8+1
  404  Not Found [IP: 130.89.148.12 80]
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Is there any work around to get packages installed required for
letsencrypt? Thanks.

Same issue if I run certbot-auto certonly mydomain.net

Regards,
Amey.