Need help reinstalling Unity (Uninstalled by accident)

[asad.bukhari]

I was learning Terminal codes and to practice wanted to uninstall compiz (CCSM). I was stupid and put 'compiz' as the program into the terminal. I hadnt realized what I had done until I restarted.

I have no UI when logging into my Ubuntu 11.10. There is a terminal box. I tried installing unity again using the code but it is unable to fetch the archives, or something along that line.

Can anyone help me get Unity back?

[JRV]

try:
sudo apt-get install ubuntu-desktop

[asad.bukhari]

I used
dpkg -l | grep compiz to confirm that I do not have compiz.

I tried
unity --replace as well as
unity --reset
Both informed me that unity is not installed.

When I try
sudo apt-get install compiz or
sudo apt-get install unity or
sudo apt-get install ubuntu-desktop I get the same error
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?

The core of my problem is the error. What is it and how do I get around it?

[LinuxFan999]

The error message suggests to run apt-get update. Try running that command, then try installing Compiz and Unity again.

[asad.bukhari]

I entered
sudo apt-get update
but only receive further errors

W: Failed to fetch http://[Several different websites] Could not resolve the archive

W: Some index files failed to download. They have been ignored, or old ones used instead.
The several different websites were:
archives.canonical.com
security.ubuntu.com
extras.ubuntu.com
us.archive.ubuntu.com
deb.opera.com

I cannot post the actual code b/c I have no means to do so. I return to my windows partition to post here.

Is this a major issue?
Is there a way to resolve it?

[bluexrider]

sudo apt-get autoremove
sudo apt-get upgrade--fix-broken

[asad.bukhari]

sudo apt-get autoremove

Did a lot.

However,

sudo apt-get upgrade--fix-broken
Resulted in:

Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove & 0 not upgraded

I tried to install unity, compiz, etc but still had the same error.
Now what?

[asad.bukhari]

Does anyone else know a solution to this?