Unable to update distribution

Please read this guide:

https://help.ubuntu.com/community/PinningHowto

sudo apt-get update && sudo apt-get upgrade

sudo apt-get dist-upgrade

I went through both methods mentioned, and xserver-org was updated. Strangely, it was not showing a lock in the Package Manager, but I updated it anyway. I also checked xserver-xorg*, fglrx*, xorg-driver-fglrx, libdrm2, gnome-session, and fast-user-switch-applet packages (as was mentioned in the original tutorial) and none displayed a lock on them. I tried to upgrade, and I got the same error. Another package was held back from being updated (gstreamer bad plugins) I upgraded and tried the whole song and dance again; and again the same error.

At present, my system is up to date according to the Update Manager.

What do you mean by "At present, my system is up to date according to the Update Manager" ?

I originally thought that perhaps I was unable to upgrade my distro due to held packages, however, after removing the packages that I knew were held and updating everything, in Update Manager it says that my system is up to date and there are no visible packages being held back.

Then I guess this issue is solved??

If so, please set the thread status to "solved"

As I mentioned previously, I am unfortunately still unable to upgrade my distro.

Don't know!
Under Synaptic, could you deactivate all "stores" except official one of Ubuntu project (sorry, I don't know how to translate "dépot").
Usually, it is done automatically.

I think I understand what you mean, but I am unsure as to how to do that in Synaptic. Could you list it step by step?

System->Administration->Synaptic Package Manager
Settings->Repositories
Other Software

I assume that on mine "Other Software" is called "Third-Party Software". I disabled all those that were active by unchecking them in their box, reloaded, closed synaptic, updated, and the same problem occurred >_<

I have found in a forum this list of commands, that I have already seen elsewhere.
So I think you can try it.

apt-get clean
apt-get auto clean
apt-get update
apt-get upgrade
apt-get dist-upgrade

Sorry for the belated response; I've been really busy the past few days. After going through the commands, nothing really happened. Here is the output, for whatever it may be worth.

kymus@Shouxing:~$ sudo apt-get clean
[sudo] password for kymus:
kymus@Shouxing:~$ sudo apt-get autoclean
Reading package lists... Done
Building dependency tree
Reading state information... Done
kymus@Shouxing:~$ sudo apt-get update
Ign http://apt.boxee.tv jaunty Release.gpg
Ign http://apt.boxee.tv jaunty/main Translation-en_US
Ign http://apt.boxee.tv jaunty Release
Ign http://apt.boxee.tv jaunty/main Packages
Hit http://us.archive.ubuntu.com jaunty Release.gpg
Ign http://us.archive.ubuntu.com jaunty/main Translation-en_US
Hit http://archive.canonical.com jaunty Release.gpg
Ign http://archive.canonical.com jaunty/partner Translation-en_US
Hit http://security.ubuntu.com jaunty-security Release.gpg
Ign http://security.ubuntu.com jaunty-security/main Translation-en_US
Hit http://archive.ubuntu.com jaunty-backports Release.gpg
Ign http://archive.ubuntu.com jaunty-backports/main Translation-en_US
Hit http://ppa.launchpad.net jaunty Release.gpg
Ign http://ppa.launchpad.net jaunty/main Translation-en_US
Ign http://archive.ubuntu.com jaunty-backports/restricted Translation-en_US
Ign http://archive.ubuntu.com jaunty-backports/universe Translation-en_US
Ign http://archive.ubuntu.com jaunty-backports/multiverse Translation-en_US
Hit http://archive.ubuntu.com jaunty-updates Release.gpg
Ign http://archive.ubuntu.com jaunty-updates/universe Translation-en_US
Ign http://archive.ubuntu.com jaunty-updates/multiverse Translation-en_US
Hit http://archive.ubuntu.com jaunty-security Release.gpg
Ign http://archive.ubuntu.com jaunty-security/main Translation-en_US
Ign http://archive.ubuntu.com jaunty-security/restricted Translation-en_US
Ign http://security.ubuntu.com jaunty-security/restricted Translation-en_US
Ign http://security.ubuntu.com jaunty-security/universe Translation-en_US
Ign http://security.ubuntu.com jaunty-security/multiverse Translation-en_US
Hit http://security.ubuntu.com jaunty-security Release
Get:1 http://ppa.launchpad.net jaunty Release.gpg [307B]
Ign http://ppa.launchpad.net jaunty/main Translation-en_US
Hit http://ppa.launchpad.net jaunty Release.gpg
Ign http://ppa.launchpad.net jaunty/main Translation-en_US
Hit http://ppa.launchpad.net jaunty Release
Ign http://archive.ubuntu.com jaunty-security/universe Translation-en_US
Ign http://apt.boxee.tv jaunty/main Packages
Ign http://archive.ubuntu.com jaunty-security/multiverse Translation-en_US
Hit http://archive.ubuntu.com jaunty-backports Release
Hit http://archive.ubuntu.com jaunty-updates Release
Hit http://archive.ubuntu.com jaunty-security Release
Err http://apt.boxee.tv jaunty/main Packages
  403 Forbidden
Get:2 http://ppa.launchpad.net jaunty Release [74.7kB]
Hit http://ppa.launchpad.net jaunty Release
Hit http://archive.canonical.com jaunty Release
Ign http://us.archive.ubuntu.com jaunty/restricted Translation-en_US
Ign http://us.archive.ubuntu.com jaunty/universe Translation-en_US
Ign http://us.archive.ubuntu.com jaunty/multiverse Translation-en_US
Hit http://us.archive.ubuntu.com jaunty-updates Release.gpg
Ign http://us.archive.ubuntu.com jaunty-updates/main Translation-en_US
Ign http://us.archive.ubuntu.com jaunty-updates/restricted Translation-en_US
Ign http://ppa.launchpad.net jaunty Release
Hit http://archive.ubuntu.com jaunty-backports/main Packages
Hit http://ppa.launchpad.net jaunty/main Packages
Hit http://us.archive.ubuntu.com jaunty Release
Hit http://archive.ubuntu.com jaunty-backports/restricted Packages
Hit http://archive.ubuntu.com jaunty-backports/universe Packages
Hit http://archive.ubuntu.com jaunty-backports/multiverse Packages
Hit http://archive.ubuntu.com jaunty-backports/main Sources
Hit http://archive.ubuntu.com jaunty-backports/restricted Sources
Hit http://archive.ubuntu.com jaunty-backports/universe Sources
Hit http://ppa.launchpad.net jaunty/main Packages
Hit http://ppa.launchpad.net jaunty/main Sources
Hit http://ppa.launchpad.net jaunty/main Packages
Hit http://ppa.launchpad.net jaunty/main Sources
Hit http://archive.canonical.com jaunty/partner Packages
Hit http://archive.ubuntu.com jaunty-backports/multiverse Sources
Hit http://archive.ubuntu.com jaunty-updates/universe Packages
Hit http://archive.ubuntu.com jaunty-updates/multiverse Packages
Hit http://archive.ubuntu.com jaunty-updates/universe Sources
Hit http://archive.ubuntu.com jaunty-updates/multiverse Sources
Hit http://security.ubuntu.com jaunty-security/main Packages
Hit http://archive.ubuntu.com jaunty-security/main Packages
Hit http://archive.ubuntu.com jaunty-security/restricted Packages
Hit http://archive.ubuntu.com jaunty-security/universe Packages
Hit http://archive.ubuntu.com jaunty-security/multiverse Packages
Hit http://archive.ubuntu.com jaunty-security/main Sources
Hit http://archive.ubuntu.com jaunty-security/restricted Sources
Hit http://security.ubuntu.com jaunty-security/restricted Packages
Hit http://security.ubuntu.com jaunty-security/restricted Sources
Hit http://security.ubuntu.com jaunty-security/main Sources
Hit http://us.archive.ubuntu.com jaunty-updates Release
Hit http://archive.ubuntu.com jaunty-security/universe Sources
Hit http://archive.ubuntu.com jaunty-security/multiverse Sources
Hit http://security.ubuntu.com jaunty-security/multiverse Sources
Hit http://security.ubuntu.com jaunty-security/universe Sources
Hit http://security.ubuntu.com jaunty-security/universe Packages
Hit http://security.ubuntu.com jaunty-security/multiverse Packages
Hit http://us.archive.ubuntu.com jaunty/main Packages
Hit http://us.archive.ubuntu.com jaunty/restricted Packages
Hit http://us.archive.ubuntu.com jaunty/restricted Sources
Hit http://us.archive.ubuntu.com jaunty/main Sources
Hit http://us.archive.ubuntu.com jaunty/multiverse Sources
Hit http://us.archive.ubuntu.com jaunty/universe Sources
Hit http://us.archive.ubuntu.com jaunty/universe Packages
Hit http://us.archive.ubuntu.com jaunty/multiverse Packages
Hit http://us.archive.ubuntu.com jaunty-updates/main Packages
Hit http://us.archive.ubuntu.com jaunty-updates/restricted Packages
Hit http://us.archive.ubuntu.com jaunty-updates/main Sources
Hit http://us.archive.ubuntu.com jaunty-updates/restricted Sources
Fetched 308B in 1s (254B/s)
W: GPG error: http://ppa.launchpad.net jaunty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 9F10E6AE9317790E
W: Failed to fetch http://apt.boxee.tv/dists/jaunty/main/binary-i386/Packages 403 Forbidden

E: Some index files failed to download, they have been ignored, or old ones used instead.
kymus@Shouxing:~$ sudo apt-get dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

Should I try doing this again disabling 3rd party software?

Should I try doing this again disabling 3rd party software? Yes, it could help.