Unable to upgrade to 13.10

[Shashank Vyas]

I tried upgrading the ubuntu from 13.04 to 13.10. But I am unable to.

I also tried command do-release-upgrade but no luck.

Got the below error:

Could not calculate the upgrade

An unresolvable problem occurred while calculating the upgrade.

This can be caused by:
* Upgrading to a pre-release version of Ubuntu
* Running the current pre-release version of Ubuntu
* Unofficial software packages not provided by Ubuntu

If none of this applies, then please report this bug using the
command 'ubuntu-bug ubuntu-release-upgrader-core' in a terminal.

Restoring original system state

Aborting

Also I cannot update my ubuntu 13.04 coz system updates are deferred. Got 404 for all of them. S.O.S.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: ubuntu-release-upgrader-core 1:0.192.13
ProcVersionSignature: Ubuntu 3.8.0-35.50-generic 3.8.13.13
Uname: Linux 3.8.0-35-generic i686
NonfreeKernelModules: nvidia
ApportVersion: 2.9.2-0ubuntu8.5
Architecture: i386
CrashDB: ubuntu
Date: Fri Jun 27 20:01:21 2014
InstallationDate: Installed on 2012-06-09 (747 days ago)
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release i386 (20120423)
MarkForUpload: True
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to raring on 2014-06-27 (0 days ago)

[Seth Arnold (seth-arnold)]

Thanks for taking the time to report this bug and helping to make Ubuntu better. We appreciate the difficulties you are facing, but this appears to be a "regular" (non-security) bug. I have unmarked it as a security issue since this bug does not show evidence of allowing attackers to cross privilege boundaries nor directly cause loss of data/privacy. Please feel free to report any other bugs you may find.

[Seth Arnold (seth-arnold)]

On a first guess, I'd try disabling your PPAs and trying again.

Thanks