obrigado pelo retorno...
o que aconteceu abaixo....
paulo@paulo-virtual-machine:~$ sudo apt-get update
E: Tipo 'http://repogen.simplylinux.ch/' não é conhecido na linha 64 na lista de fontes /etc/apt/sources.list
E: A lista de fontes não pode ser lida.
paulo@paulo-virtual-machine:~$ sudo apt-get update
E: Tipo 'http://repogen.simplylinux.ch/' não é conhecido na linha 64 na lista de fontes /etc/apt/sources.list
E: A lista de fontes não pode ser lida.
paulo@paulo-virtual-machine:~$ sudo apt-get upgrade
Lendo listas de pacotes... Pronto
Construindo árvore de dependências
Lendo informação de estado... Pronto
Os pacotes a seguir serão mantidos em suas versões atuais:
libsyncdaemon-1.0-1 linux-generic linux-headers-generic linux-image-generic
python-ubuntuone-client ubuntuone-client ubuntuone-client-gnome
Os pacotes a seguir serão atualizados:
acpid app-install-data app-install-data-partner apport apport-gtk apt
apt-transport-https apt-utils aptdaemon aptdaemon-data apturl apturl-common
bamfdaemon banshee banshee-extension-soundmenu
banshee-extension-ubuntuonemusicstore bind9-host binutils bzip2
ca-certificates compiz compiz-core compiz-gnome compiz-plugins
compiz-plugins-main cups cups-bsd cups-client cups-common cups-ppdc dbus
dbus-x11 dnsutils dpkg dpkg-dev empathy empathy-common evince evince-common
file-roller firefox firefox-globalmenu firefox-gnome-support foo2zjs
foomatic-filters gdm gir1.2-panelapplet-3.0 gir1.2-soup-2.4 glib-networking
gnome-keyring gnome-nettool gnome-panel gnome-panel-bonobo gnome-panel-data
gnome-power-manager gnome-session gnome-session-bin gnome-session-common
gnome-user-guide gstreamer0.10-tools gvfs gvfs-backends gvfs-fuse gwibber
gwibber-service gwibber-service-facebook gwibber-service-identica
gwibber-service-twitter initramfs-tools initramfs-tools-bin initscripts
isc-dhcp-client isc-dhcp-common language-selector-common
language-selector-gnome libarchive1 libbamf0 libbind9-60 libbz2-1.0 libcups2
libcupscgi1 libcupsdriver1 libcupsimage2 libcupsmime1 libcupsppdc1
libcurl3-gnutls libdbus-1-3 libdbusmenu-glib3 libdbusmenu-gtk3
libdecoration0 libdns69 libdpkg-perl libevdocument3 libevview3 libfreetype6
libgcr0 libgksu2-0 libgl1-mesa-dri libgl1-mesa-glx libglu1-mesa libgp11-0
libgpod-common libgpod4 libgssapi-krb5-2 libgstreamer0.10-0 libgvfscommon0
libgweather-common libgweather1 libimobiledevice2 libisc62 libisccc60
libisccfg62 libjasper1 libk5crypto3 libkrb5-3 libkrb5support0 libldap-2.4-2
liblircclient0 liblwres60 libnux-0.9-0 libnux-0.9-common
liboverlay-scrollbar-0.1-0 libpam-gnome-keyring libpam-modules
libpam-modules-bin libpam-runtime libpam0g libpanel-applet-3-0
libpanel-applet2-0 libperl5.10 libplymouth2 libpng12-0 libpoppler-glib6
libpoppler13 libpulse-browse0 libpulse-mainloop-glib0 libpulse0
libpurple-bin libpurple0 libreoffice-emailmerge libreoffice-style-human
librsvg2-2 librsvg2-common libsmbclient libsndfile1 libsoup-gnome2.4-1
libsoup2.4-1 libt1-5 libtelepathy-logger2 libwbclient0 libxfont1 libxml2
libxml2-utils linux-libc-dev logrotate nautilus-sendto
nautilus-sendto-empathy ntpdate nux-tools nvidia-common overlay-scrollbar
perl perl-base perl-modules plymouth plymouth-label
plymouth-theme-ubuntu-logo plymouth-theme-ubuntu-text poppler-utils
pulseaudio pulseaudio-esound-compat pulseaudio-module-bluetooth
pulseaudio-module-gconf pulseaudio-module-x11 pulseaudio-utils python-apport
python-apt python-apt-common python-aptdaemon python-aptdaemon-gtk
python-aptdaemon.gtk3widgets python-aptdaemon.gtkwidgets python-cupshelpers
python-glade2 python-gobject python-gobject-cairo python-gtk2 python-libxml2
python-papyon python-problem-report python-ubuntuone-control-panel
python-ubuntuone-storageprotocol rdesktop rsyslog samba-common
samba-common-bin shotwell smbclient software-center sudo
system-config-printer-common system-config-printer-gnome
system-config-printer-udev sysv-rc sysvinit-utils telepathy-logger tomboy
ttf-opensymbol ubuntu-docs ubuntu-sso-client ubuntuone-control-panel
ubuntuone-control-panel-gtk udisks unity unity-common
unity-place-applications unity-place-files uno-libs3 update-manager
update-manager-core update-notifier update-notifier-common ure
usb-creator-common usb-creator-gtk vino whois x11-common xorg xserver-common
xserver-xorg xserver-xorg-core xserver-xorg-input-all
xserver-xorg-input-synaptics xserver-xorg-video-all xserver-xorg-video-ati
xserver-xorg-video-intel xserver-xorg-video-radeon xul-ext-ubufox
239 pacotes atualizados, 0 pacotes novos instalados, 0 a serem removidos e 7 não atualizados.
É preciso baixar 16,4 MB/115 MB de arquivos.
Depois desta operação, 11,4 MB adicionais de espaço em disco serão usados.
Você quer continuar [S/n]? S
Err http://br.archive.ubuntu.com/ubuntu/ natty-updates/main libxml2 i386 2.7.8.dfsg-2ubuntu0.1
404 Not Found
Err http://security.ubuntu.com/ubuntu/ natty-security/main libxml2 i386 2.7.8.dfsg-2ubuntu0.1
404 Not Found [IP: 91.189.92.166 80]
Err http://security.ubuntu.com/ubuntu/ natty-security/main libt1-5 i386 5.1.2-3ubuntu0.11.04.1
404 Not Found [IP: 91.189.92.166 80]
Err http://security.ubuntu.com/ubuntu/ natty-security/main firefox-globalmenu i386 8.0+build1-0ubuntu0.11.04.3
404 Not Found [IP: 91.189.92.166 80]
Err http://security.ubuntu.com/ubuntu/ natty-security/main firefox i386 8.0+build1-0ubuntu0.11.04.3
404 Not Found [IP: 91.189.92.166 80]
Err http://security.ubuntu.com/ubuntu/ natty-security/main firefox-gnome-support i386 8.0+build1-0ubuntu0.11.04.3
404 Not Found [IP: 91.189.92.166 80]
Err http://security.ubuntu.com/ubuntu/ natty-security/main libxml2-utils i386 2.7.8.dfsg-2ubuntu0.1
404 Not Found [IP: 91.189.92.166 80]
Err http://security.ubuntu.com/ubuntu/ natty-security/main python-libxml2 i386 2.7.8.dfsg-2ubuntu0.1
404 Not Found [IP: 91.189.92.166 80]
Err http://security.ubuntu.com/ubuntu/ natty-security/main xul-ext-ubufox all 0.9.2-0ubuntu0.11.04.2
404 Not Found [IP: 91.189.92.166 80]
Falhou ao buscar http://security.ubuntu.com/ubuntu/pool/main/libx/libxml2/libxml2_2.7.8.dfsg-2ubuntu0.1_i386.deb 404 Not Found [IP: 91.189.92.166 80]
Falhou ao buscar http://security.ubuntu.com/ubuntu/pool/main/t/t1lib/libt1-5_5.1.2-3ubuntu0.11.04.1_i386.deb 404 Not Found [IP: 91.189.92.166 80]
Falhou ao buscar http://security.ubuntu.com/ubuntu/pool/main/f/firefox/firefox-globalmenu_8.0+build1-0ubuntu0.11.04.3_i386.deb 404 Not Found [IP: 91.189.92.166 80]
Falhou ao buscar http://security.ubuntu.com/ubuntu/pool/main/f/firefox/firefox_8.0+build1-0ubuntu0.11.04.3_i386.deb 404 Not Found [IP: 91.189.92.166 80]
Falhou ao buscar http://security.ubuntu.com/ubuntu/pool/main/f/firefox/firefox-gnome-support_8.0+build1-0ubuntu0.11.04.3_i386.deb 404 Not Found [IP: 91.189.92.166 80]
Falhou ao buscar http://security.ubuntu.com/ubuntu/pool/main/libx/libxml2/libxml2-utils_2.7.8.dfsg-2ubuntu0.1_i386.deb 404 Not Found [IP: 91.189.92.166 80]
Falhou ao buscar http://security.ubuntu.com/ubuntu/pool/main/libx/libxml2/python-libxml2_2.7.8.dfsg-2ubuntu0.1_i386.deb 404 Not Found [IP: 91.189.92.166 80]
Falhou ao buscar http://security.ubuntu.com/ubuntu/pool/main/u/ubufox/xul-ext-ubufox_0.9.2-0ubuntu0.11.04.2_all.deb 404 Not Found [IP: 91.189.92.166 80]
E: Impossível buscar alguns arquivos, talvez executar apt-get update ou tentar com --fix-missing?
paulo@paulo-virtual-machine:~$