can't update to last kubuntu version

Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/libx/libxdmcp/libxdmcp6_1.1.1-1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/libx/libxdmcp/libxdmcp6_1.1.1-1_i386.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/d/dbus-python/python-dbus-dev_1.1.1-1ubuntu0.1_all.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/d/dbus-python/python-dbus_1.1.1-1ubuntu0.1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/d/dbus-python/python3-dbus_1.1.1-1ubuntu0.1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/libx/libxmu/libxmu6_1.1.1-1_i386.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/libx/libxmu/libxmu6_1.1.1-1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/libf/libfontenc/libfontenc1_1.1.1-1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/libx/libxmu/libxmuu1_1.1.1-1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/libx/libxslt/libxslt1.1_1.1.26-14ubuntu0.1_i386.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/libx/libxslt/libxslt1.1_1.1.26-14ubuntu0.1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/libx/libxcursor/libxcursor1_1.1.13-1ubuntu0.12.10.1_i386.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/libx/libxcursor/libxcursor1_1.1.13-1ubuntu0.12.10.1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/l/lightdm/liblightdm-gobject-1-0_1.4.0-0ubuntu2_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/l/lightdm/liblightdm-qt-2-0_1.4.0-0ubuntu2_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/main/p/portaudio19/libportaudio2_19+svn20111121-1build1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/v/virtualbox/virtualbox-qt_4.1.18-dfsg-1ubuntu1.2_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/v/virtualbox/virtualbox_4.1.18-dfsg-1ubuntu1.2_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/v/virtualbox/virtualbox-dkms_4.1.18-dfsg-1ubuntu1.2_all.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/a/akonadi-facebook/akonadi-facebook_0.0git20120712-0ubuntu2_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/k/ktp-common-internals/libktpcommoninternalsprivate3_0.5.1-0ubuntu1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/k/ktp-text-ui/libktpchat0_0.5.1-0ubuntu1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/k/ktp-text-ui/plasma-widget-telepathy-chat_0.5.1-0ubuntu1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/k/ktorrent/ktorrent_4.2.1-1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/k/ktorrent/ktorrent-data_4.2.1-1_all.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/libk/libktorrent/libktorrent4_1.2.1-1_amd64.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/libk/libktorrent/libktorrent-l10n_1.2.1-1_all.deb Tamanho incorreto
Failed to fetch http://br.archive.ubuntu.com/ubuntu/pool/universe/m/muon/libmuonprivate1_1.4.1-0ubuntu1.1_amd64.deb Tamanho incorreto