kernel panic; not syncing: VFS: unable to mount root fs on unknown block
 

When trying to boot PCLinux 2010 on an external esata drive enclosure with a 2009 store built desktop computer it results in this error message; kernel panic; not syncing: VFS: unable to mount root fs on unknown block (0,0), and this too; cannot open root device "UUID= (some numbers and letters) or unknown block (0,0) please append a correct root= boot option. Does it make a possible cause for this issue due to the Linux installs were done with a older computer with way different hardware components, (a 2006 Gateway) ? I have a total of 6 versions of Linux installed on that 500 Gb external hard drive, and several do boot okay; (Fedora 15, Mint 9,Kubuntu 10.04,), and my internal PC drive has Ubuntu 10.04 and 12.04 installed.

do that. in grub

kernel your_kernel root=/dev/something