Trouble installing apps in my ubuntu server

[reghu007]

I am not able to install any apps in my ubuntu server, for example when i try installing swi-prolog, i get the following error message:

:~# apt-get install swi-prolog
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
libgmp3c2
Suggested packages:
prolog-el
Recommended packages:
swi-prolog-doc swi-prolog-xpce
The following NEW packages will be installed:
libgmp3c2 swi-prolog
0 upgraded, 2 newly installed, 0 to remove and 167 not upgraded.
Need to get 1711kB of archives.
After unpacking 4649kB of additional disk space will be used.
Do you want to continue [Y/n]? y
WARNING: The following packages cannot be authenticated!
libgmp3c2 swi-prolog
Install these packages without verification [y/N]? y
Err http://us.archive.ubuntu.com gutsy/main libgmp3c2 2:4.2.1+dfsg-5ubuntu4
404 Not Found [IP: 91.189.88.140 80]
Err http://us.archive.ubuntu.com gutsy/universe swi-prolog 5.6.14-1
404 Not Found [IP: 91.189.88.140 80]
Failed to fetch http://us.archive.ubuntu.com/ubuntu/pool/main/g/gmp/libgmp3c2_4.2.1+dfsg-5ubuntu4_i386.deb 404 Not Found [IP: 91.189.88.140 80]
Failed to fetch http://us.archive.ubuntu.com/ubuntu/pool/universe/s/swi-prolog/swi-prolog_5.6.14-1_i386.deb 404 Not Found [IP: 91.189.88.140 80]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?

Any pointers please???

[Partyboi2]

Hi, gutsy has reached its end of life, you would be better of upgrading to a later release of Ubuntu so you can get the security updates.
You can also backup and replace your sources.list with these repos to install packages (not updates) for Gutsy.

deb http://old-releases.ubuntu.com/ubuntu/ gutsy main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu/ gutsy-updates main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu/ gutsy-security main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu/ gutsy-backports main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu/ gutsy-backports main/debian-installer
deb-src http://old-releases.ubuntu.com/ubuntu/ gutsy-backports main restricted universe multiverse