I gor error 15 when booting my opensuse 11.1

I get this error massage at booting up my opensuse 11.1:
kernel (hd0,5)/mnt/boot/initrd-26.27.7-9pae root=/dev/disk/by-id/ata-ST380815AS_9QZBXKVG-part6 vga=0x317
Error 15: file not found
:
Why this error happened? What is the solution? Thanks.

grub manual says:

15 : File not foundThis error is returned if the specified file name cannot be found, but everything else (like the disk/partition info) is OK.

Have updated the kernel recently?

Take a look at the bold section in the quote, this should never be like this in a default setup. If you have not customized partitioning, this might be the solution:
In the GRUB menu screen, hit Esc.
A text based version of the menu will be displayed. Select your boot option, then hit ‘e’ to edit, select the line that has the bold part in it and remove the bolded part, i.e. “/mnt”, no more, no less.
After doing so, hit Enter.

If so, you have to make things persistent by recreating a bootloader config from Yast - System

I have followed your suggestion. Still not work. Then i boot from installation cd and choose repair boot section. After some failure, i started to make from scratch. And success…
Thanks.

Glad you got it sorted.