cannot upgrade to ubuntu 14.10

[Sifar]

both software updater and terminal do-release-upgrade show error in between saying "some packages disabled in sources.list. you can enable them in software-properties.....". later they stop downloading with error.....

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: ubuntu-release-upgrader-core 1:0.220.7
ProcVersionSignature: Ubuntu 3.19.0-26.27~14.04.1-generic 3.19.8-ckt4
Uname: Linux 3.19.0-26-generic i686
ApportVersion: 2.14.1-0ubuntu3.12
Architecture: i386
CrashDB: ubuntu
CurrentDesktop: Unity
Date: Thu Aug 13 01:49:22 2015
InstallationDate: Installed on 2015-08-11 (1 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta i386 (20150805)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to trusty on 2015-08-12 (0 days ago)
mtime.conffile..etc.update.manager.release.upgrades: 2015-08-12T22:46:21.735566