[sagher]

Hi experts. as you all know i have some critical issues in past with my OS. and i reinstall it as suggest. but after a month i try to use again apt-get update and upgrade command and found these issues. 

Code: (Select All)

Err http://ftp.debian.org jessie-updates/main amd64 Packages
  404  Not Found
Err http://ftp.debian.org jessie-updates/contrib amd64 Packages
  404  Not Found
Err http://ftp.debian.org jessie-updates/non-free amd64 Packages
  404  Not Found
W: Failed to fetch http://ftp.debian.org/debian/dists/jessie-updates/main/binary-amd64/Packages  404  Not Found

W: Failed to fetch http://ftp.debian.org/debian/dists/jessie-updates/contrib/binary-amd64/Packages  404  Not Found

W: Failed to fetch http://ftp.debian.org/debian/dists/jessie-updates/non-free/binary-amd64/Packages  404  Not Found

E: Some index files failed to download. They have been ignored, or old ones used instead.

what does it means?