mitydsp@mitydsp-dev:~$ sudo apt-get install putty
[sudo] password for mitydsp: 
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following extra packages will be installed:
  putty-tools
The following NEW packages will be installed:
  putty putty-tools
0 upgraded, 2 newly installed, 0 to remove and 274 not upgraded.
Need to get 1,087kB of archives.
After this operation, 2,736kB of additional disk space will be used.
Do you want to continue [Y/n]? y
WARNING: The following packages cannot be authenticated!
  putty-tools putty
Install these packages without verification [y/N]? y
Err http://us.archive.ubuntu.com/ubuntu/ lucid/universe putty-tools 0.60+2009-11-22-1
  404  Not Found [IP: 91.189.91.26 80]
Err http://us.archive.ubuntu.com/ubuntu/ lucid/universe putty 0.60+2009-11-22-1
  404  Not Found [IP: 91.189.91.26 80]
Failed to fetch http://us.archive.ubuntu.com/ubuntu/pool/universe/p/putty/putty-tools_0.60+2009-11-22-1_i386.deb  404  Not Found [IP: 91.189.91.26 80]
Failed to fetch http://us.archive.ubuntu.com/ubuntu/pool/universe/p/putty/putty_0.60+2009-11-22-1_i386.deb  404  Not Found [IP: 91.189.91.26 80]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?
mitydsp@mitydsp-dev:~$