Ubuntu-12.04 "Packages was corrupt"

When you install Ubuntu-12.04.1-server-amd64 from Kickstart server unattended (and probably ubuntu-12.04-server-amd64 as well) you'll get an error message that the "Packages file was corrupt" and the installation stops.  If you hit continue button it goes on.

Here is the file in Ubuntu distro that causes the error:
ubuntu-12.04/dists/precise/restricted/binary-amd64/Packages.gz

It's a bug.  Few people reported it to Ubuntu team but Ubuntu guys (like Fabio Marconi)  don't seem to care and just closed the tickets.
https://bugs.launchpad.net/ubuntu/+source/debian-installer/+bug/1023069

Solution:

1.  Unzip that file manually in your Kickstart installation directory.  E.g.:
/srv/kickstart/ubuntu-12.04/dists/precise/restricted/binary-amd64# gunzip Packages.gz

2.  Copy the original file from your iso image directory to the same location:
/srv/kickstart/ubuntu-12.04/dists/precise/restricted/binary-amd64/

You should have 3 files in there:

-r--r--r-- 1 root root   0 Nov 15 17:30 Packages
-r--r--r-- 1 root root  20 Nov 15 17:31 Packages.gz
-rw-r--r-- 1 root root 103 Nov 15 17:30 Release

That's it - now the installer will be happy.



Reason as far as I understand it.
The installer unzips those file during the installation.  After Packages.gz gets unzipped, the size of the new file shows 0 (because it's an emtpy file to start with).  The installer "thinks" that the file is corrupt and stops the installation process.  When you give it unzipped version of the same empty file, it happily continues the installation.