Also Unable to upgrade from Mint 21.3 to Mint 22

[starfoxx82]

Hi,

i've read the issues on your repo. I have also problems to upgrade Linux Mint 21.3 to 22 with mintupgrade tool. I have checked my official-packages-repositories.list multiple times. I got follow message, when i run the check.py.
It looks like the Issue #10 .

sudo /usr/lib/linuxmint/mintupgrade/checks.py
Die folgenden Probleme wurden gefunden:
    ['https://ftp.halifax.rwth-aachen.de/linuxmint/ ist nicht erreichbar']
    ['http://archive.ubuntu.com/ubuntu unterstützt noble nicht']
    ['http://archive.ubuntu.com/ubuntu unterstützt noble-updates nicht']
    ['http://security.ubuntu.com/ubuntu unterstützt noble-security nicht']
    ['http://archive.ubuntu.com/ubuntu unterstützt noble-backports nicht']

I changed the ftp.halifax...... in packages.linuxmint.com and fastly.linuxmint.io but the failure won't gone. My system is behind an proxy. I've configure proxy settings in synaptic, in the /etc/apt/apt.conf.d/01proxy with the following settings:

Acquire::https::proxy "http://111.122.133.144:8080/";
Acquire::http::proxy "http://111.122.133.144:8080/";
Acquire::ftp::proxy "http://111.122.133.144:8080/";

and with env-variables for root and also my username:

tfp_proxy=http://111.122.133.144:8080
http_proxy=http://111.122.133.144:8080
https_proxy=http://111.122.133.144:8080
FTP_PROXY= ...
HTTP_PROXY= ...
HTTPS_PROXY= ...

The wget - configurations:

cat /etc/wgetrc
...
https_proxy = http://111.122.133.144:8080
http_proxy = http://111.122.133.144:8080
ftp_proxy = http://111.122.133.144:8080

use_proxy = on
...

The "normal" package installations with apt install <package_name> has no problems.

inxi -r outputs:

inxi -r
Repos:
  No active apt repos in: /etc/apt/sources.list
  No active apt repos in: /etc/apt/sources.list.d/additional-repositories.list
  Active apt repos in: /etc/apt/sources.list.d/official-package-repositories.list
    1: deb https://ftp.halifax.rwth-aachen.de/linuxmint/ virginia main upstream import backport
    2: deb http://archive.ubuntu.com/ubuntu jammy main restricted universe multiverse
    3: deb http://archive.ubuntu.com/ubuntu jammy-updates main restricted universe multiverse
    4: deb http://security.ubuntu.com/ubuntu jammy-security main restricted universe multiverse
    5: deb http://archive.ubuntu.com/ubuntu jammy-backports main restricted universe multiverse

uname:

uname -a
Linux srv-01 5.15.0-118-generic #128-Ubuntu SMP Fri Jul 5 09:28:59 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux