apt-get upgrade Ошибка 403 запрещена

Я использую Ubuntu 16.04.4 LTS.

Обновление sudo apt-get работает нормально, но когда я запускаю sudo apt-get upgrade, я получаю следующие ошибки: (ПРИМЕЧАНИЕ: я уже изменил сервер загрузки с source.list на archive.ubuntu.com вместо pt.archive .ubuntu.com)

/etc/apt# sudo apt-get upgrade --fix-missing
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following packages have been kept back:
  libdrm2 linux-generic linux-headers-generic linux-image-generic
The following packages will be upgraded:
  apache2 apache2-bin apache2-data apache2-utils apport cloud-guest-utils distro-info-data gcc-5-base grub-common grub-legacy-ec2 grub-pc grub-pc-bin grub2-common hdparm ifupdown libicu55
  libpam-modules libpam-modules-bin libpam-runtime libpam0g libpci3 libperl5.22 libplymouth4 libpython3.5 libpython3.5-minimal libpython3.5-stdlib libseccomp2 libssl1.0.0 libstdc++6 linux-base
  lshw lxcfs lxd lxd-client mysql-client-5.7 mysql-client-core-5.7 mysql-common mysql-server mysql-server-5.7 mysql-server-core-5.7 open-vm-tools openssl patch pciutils perl perl-base
  perl-modules-5.22 plymouth plymouth-theme-ubuntu-text python-apt-common python3-apport python3-apt python3-distupgrade python3-problem-report python3.5 python3.5-minimal snap-confine snapd
  sosreport ubuntu-core-launcher ubuntu-release-upgrader-core wget xdg-user-dirs
63 upgraded, 0 newly installed, 0 to remove and 4 not upgraded.
Need to get 15.7 MB/67.5 MB of archives.
After this operation, 3,140 kB of additional disk space will be used.
Do you want to continue? [Y/n] Y
Err:1 http/security.ubuntu.com/ubuntu xenial-security/main amd64 libpython3.5 amd64 3.5.2-2ubuntu0~16.04.4
  403  Forbidden [IP: 91.189.88.149 80]
Ign:2 http/security.ubuntu.com/ubuntu xenial-security/main amd64 python3.5 amd64 3.5.2-2ubuntu0~16.04.4
Ign:3 http//security.ubuntu.com/ubuntu xenial-security/main amd64 libpython3.5-stdlib amd64 3.5.2-2ubuntu0~16.04.4
Err:1 http//security.ubuntu.com/ubuntu xenial-security/main amd64 libpython3.5 amd64 3.5.2-2ubuntu0~16.04.4
  403  Forbidden [IP: 91.189.88.149 80]

......................

update-initramfs: Generating /boot/initrd.img-4.4.0-62-generic
W: mdadm: /etc/mdadm/mdadm.conf defines no arrays.
E: Failed to fetch http//security.ubuntu.com/ubuntu/pool/main/p/python3.5/libpython3.5_3.5.2-2ubuntu0~16.04.4_amd64.deb  403  Forbidden [IP: 91.189.88.149 80]

E: Failed to fetch http//security.ubuntu.com/ubuntu/pool/main/p/python3.5/python3.5_3.5.2-2ubuntu0~16.04.4_amd64.deb  403  Forbidden [IP: 91.189.88.149 80]

E: Failed to fetch http//security.ubuntu.com/ubuntu/pool/main/p/python3.5/libpython3.5-stdlib_3.5.2-2ubuntu0~16.04.4_amd64.deb  403  Forbidden [IP: 91.189.88.149 80]

E: Failed to fetch http//security.ubuntu.com/ubuntu/pool/main/p/python3.5/python3.5-minimal_3.5.2-2ubuntu0~16.04.4_amd64.deb  403  Forbidden [IP: 91.189.88.149 80]

Спасибо! R.L.