Comment 8 for bug 557130

This bug is a duplicate of bug #431307, first reported on 2009-09-17 and still open; it renders the distro uninstallable on many popular systems, is relatively easy to fix, yet it still was not fixed in the final lucid release, 7.5 months later... come on guys, this is frustrating.

At any rate, there is a work-around: copy atl1c.ko from the lucid desktop ISO to your alternate installation media, or somewhere else that can be made accessible to the machine being installed.

Roughly,

mkdir /tmp/mount-1
mkdir /tmp/mount-2
sudo mount -t iso9660 -o ro,loop /your/path/to/ubuntu-10.04-desktop-amd64.iso /tmp/mount-1
sudo mount -t squashfs -o ro,loop /tmp/mount-1/casper/filesystem.squashfs /tmp/mount-2
cp -p /tmp/mount-2/lib/modules/2.6.32-21-generic/kernel/drivers/net/atl1c/atl1c.ko /your/path/to/mounted/alternate-install-media/
sudo umount /tmp/mount-2
sudo umount /tmp/mount-1
rmdir /tmp/mount-2
rmdir /tmp/mount-1

Then, when installing, switch to a different virtual-terminal (e.g. "Alt-F2"), and:
insmod /cdrom/atl1c.ko

...then proceed with installation.