To update old releases of Ubuntu os -

In the command line open below config file

vi /etc/apt/sources.list

http://in.archive.ubuntu.com/ubuntu/
http://security.ubuntu.com/ubuntu

In the place of above files i.e in.archive , security Replace with old-releases as below and save the file.

Press shift + G come to end of the file and replace as explained above

:%s/in.archive/old-releases/g
:%s/security/old-releases/g

should look like below after replacing

http://old-releases.ubuntu.com/ubuntu/

To update old releases of Ubuntu os