grub version? (1 or 2) must have been installed to the mbr of the main laptop drive, not to the mbr or /boot-partition of the "serial-ata-drive-a/b/cetera-number1/2/... ".
grub needs access to the /boot/* and/boot/grub/* -dirs and binaries
so this is a kind of "lock" for a computer also (but no-one wants this unforeseen confusion).
to manage to write a windows loading mbr at vista
i used "EasyBCD 1.7.2" that can be downloaded somewhere for the case there is only OriginalEquipmentManufacturer-DVD/CD.
it was an "nothing to loose" act but everything went fine.
btw: ubuntu is not my favorite. and as long as i can remember there is always something with grub (former graphics), lilo works also and just to have a "good looking screen" i don´t need grub. the command line is very good for experienced users, it-people or programmers.
if there is another linux partition on the internal HD then try change the entries at /boot/grub/menu.lst (grub1)from ../sdb1 to sda1 f.ex. and the long disk-by-identity (UUID) that is unique number to all the billions or tera-amounts of HD in the world.
*.10 means archive and *.04 read to me
Filesystem permissions - Wikipedia, the free encyclopedia - [ Diese Seite übersetzen ]
0 --- no permission 1 --x execute 2 -w- write 3 -wx write and execute 4 r-- read 5 r-x read and execute 6 rw- read and write 7 rwx read, write and execute ...
en.wikipedia.org/wiki/Filesystem_permissions - Im Cache