The other day I was asked to upgrade from 13.04 to 13.10, at the time I was busy and hit no. I can not upgrade/update at this point, I get (error -11) or a 404 in terminal. In the software updater I get 'failed to download repository information.'

I have tried changing my "Download From" setting to "Best" to "Main" and even a few other countries. And in "Other Software" I have tried disabling packages, but doesn't seem to help what so ever. I have tried several of the other commands to try and fix it, such as -fix missing or sudo apt-get update clean.

P.S. This has also affected my thunderbird client, I cannot send/receive emails.

Here is my error log when trying to upgrade:

jakob@Skeletor:~$ sudo update-manager -d

gpg: /tmp/tmpvejqvl/trustdb.gpg: trustdb created
gpg: /tmp/tmpnayby6/trustdb.gpg: trustdb created
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/defer/__init__.py", line 483, in _inline_callbacks
    result = gen.throw(excep)
  File "/usr/lib/python3/dist-packages/UpdateManager/backend/InstallBackendAptdaemon.py", line 86, in commit
    True, close_on_done)
  File "/usr/lib/python3/dist-packages/defer/__init__.py", line 483, in _inline_callbacks
    result = gen.throw(excep)
  File "/usr/lib/python3/dist-packages/UpdateManager/backend/InstallBackendAptdaemon.py", line 158, in _run_in_dialog
    yield trans.run()
aptdaemon.errors.TransactionFailed: Transaction failed: Package does not exist
 Package linux-headers-3.8.0-33 isn't available
gpg: /tmp/tmp3kw_hl/trustdb.gpg: trustdb created.

And let me throw in my sudo apt-get update too. Which this has been working variably too, but I don't know what to change my repositories to, and disabling does not effect:

 E: Some index files failed to download. They have been ignored, or old ones used instead.

This is the short version, but looks exactly like this fairly consistently. Sometimes it downloads, sometimes it doesn't. Sometimes it tells me I have an update, and doesn't do anything.

If it helps, I have recently had issues trying to install Samba as well, and connecting to the office's NAS Drive. Which works now, but I had to edit /etc/fstab/ and a few other things trying to get that to work as well. I understand it could also be a DNS problem, but this has been going on for a few days, as well as I've already tried changing my DNS server via my computer, however I am not allowed to alter the DNS on our company's router.