upgrade 9.10->10.04 fails to boot

[jbarntt]

Dual boot Windows XP SP3 & Ubuntu 9.10 on a single hdd, w/2 partitions. Booted to Ubuntu and upgraded online. XP boots fine, but Ubuntu, not so much; a msg about /dev not found, followed by a shell login prompt.

I suspect a grub problem, but haven't been able to find a definitive answer. Since I can at least boot XP, I do not want to do anything that would screw that up and leave me with no bootable OS.

I did the "upgrade" shortly after 10.04 was released.

Is there a way to reliably fix this w/o possibly screwing up my ability to boot XP, the only OS I can boot ?

I have no Ubuntu 10.04 disk, as I used their upgrade online option.

TIA

[DCMR2]

I have the same problem with the same software versions except I have two different disks. I gave up about two months ago because I didn't want to screw up my working OS. I did a couple of "sure fixes" that didn't. I may try downloading the 10.04 iso and burning it to see if I boot from the cd if I can fix grub. Hope someone has a solution.