So I installed Backtrack 4 Pre on my shiny new Asus Eee PC 900 the other day and to be fair everything was going well. I used Unetbooting and a spare 8gb Flash Dirve and installed the Distro onto sdb (The secondary 16Gb Flash Drive). No problems apart from the aforementioned error on boot.

modprobe FATAL could not load /lib/modules/2.6.29.4/modules.dep

Some people have reported that packing and unpacking the module does the trick, so after a short stint at the prompt I was hoping this would be fixed:

cd /boot
cp initrd.img-2.6.29.4 initrd-2.6.29.4.old (Just making a backup)
depmod -a
update-initramfs -k 2.6.29.4 -c
cd /tmp
gzip -dc /boot/initrd.img-2.6.29.4| cpio -id
touch lib/modules/2.6.29.4/modules.dep
find ./ | cpio -H newc -o > /boot/initrd.img-2.6.29.4.new
gzip /boot/initrd.img-2.6.29.4.new
cd /boot
mv initrd.img-2.6.29.4.new.gz initrd.img-2.6.29.4

Didn’t fix the problem unfortunately, but the I stumbled across a forum post over at Remote-Exploit and the following rather simple cammand fixed the whole shebang:

update-grub

And now it works like a treat! Original Post at the RE Forums here.