Comment 6 for bug 663053

That was really the reason, wrong UUID and therefore cryptsetup failed since it didn't find the correct partition. The first visible error message "cryptsetup: evms_activate is not available" was kinda misleading.

So toobuntu and Eric, check that you have correct UUID.

You can check and fix it by booting from a live CD, mount your /boot partition and then extract the initramfs (after first copying it to a temporary directory):

gunzip -c -9 initrd.img-2.6.35-22-generic | cpio -i -d -H newc --no-absolute-filenames

Check and fix conf/conf.d/cryptroot (the source parameter, I corrected the UUID by replacing it with correct /dev/sdaX).

Then pack the initramfs again:

find . -print0 | cpio --null -ov --format=newc | gzip -9 > your-new-initramfs.cpio.gz

Then backup your old initramfs and copy the new to the correct location. Reboot, and hope this fixes things also for you. :)