Size mismatch error on repository breaks apt-get

[cyberduck]

aff08ef created the issue

My 14.04 system hasn't been updating recently, apparently due to an error in cyberduck:

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Calculating upgrade... Done
The following packages have been kept back:
  linux-headers-generic linux-signed-generic linux-signed-image-generic
The following packages will be upgraded:
  apt apt-transport-https apt-utils compiz compiz-core compiz-gnome
  compiz-plugins-default curl duck firefox firefox-locale-en fonts-opensymbol
  gir1.2-networkmanager-1.0 google-chrome-stable gvfs gvfs-backends gvfs-bin
  gvfs-common gvfs-daemons gvfs-fuse gvfs-libs hhvm icedtea-6-jre-cacao
  icedtea-6-jre-jamvm icedtea-7-jre-jamvm libapt-inst1.5 libapt-pkg4.12
  libcompizconfig0 libcurl3 libcurl3-gnutls libdecoration0 libmysqlclient18
  libnm-glib-vpn1 libnm-glib4 libnm-util2 liboxideqt-qmlplugin liboxideqtcore0
  liboxideqtquick0 librados2 librbd1 libreoffice-avmedia-backend-gstreamer
  libreoffice-base-core libreoffice-calc libreoffice-common libreoffice-core
  libreoffice-draw libreoffice-gnome libreoffice-gtk libreoffice-impress
  libreoffice-math libreoffice-ogltrans libreoffice-pdfimport
  libreoffice-presentation-minimizer libreoffice-style-human
  libreoffice-writer linux-libc-dev mysql-client-5.5 mysql-client-core-5.5
  mysql-common mysql-server mysql-server-5.5 mysql-server-core-5.5
  network-manager openjdk-6-jre openjdk-6-jre-headless openjdk-6-jre-lib
  openjdk-7-jdk openjdk-7-jre openjdk-7-jre-headless oxideqt-codecs-extra
  python-compizconfig python-pip python3-uno python3-update-manager
  qtcreator-plugin-ubuntu qtcreator-plugin-ubuntu-common tcpdump tzdata
  tzdata-java ubuntu-sdk-qmake-extras uno-libs3 update-manager
  update-manager-core ure usb-creator-common usb-creator-gtk virtualbox
  virtualbox-dkms virtualbox-qt wpasupplicant xserver-xorg-video-intel
91 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.
Need to get 80.8 MB/417 MB of archives.
After this operation, 4,059 kB of additional disk space will be used.
Do you want to continue? [Y/n] Y
Fetched 80.8 MB in 1min 56s (696 kB/s)
E: Failed to fetch https://s3.amazonaws.com/repo.deb.cyberduck.io/pool/d/du/duck-4.7.17418.amd64.deb  Size mismatch

E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?

After unchecking the duck entry in software-sources application, Ubuntu updates just fine.

[cyberduck]

@ylangisc commented

Metadata fixed.