I was getting the same error, I installed ubuntu on my first hard drive (sda1, in grub hd0), and windows on my second hard drive (sdb1, in grub hd1). Ubuntu worked fine but when it tried to boot windows I would get error 21. I went into my bios setup and looked under "drives". There was SATA1 which was "on" and said "hard drive 160gb ect...." which was my linux drive. SATA2 was then went to my cd/dvd drive, SATA3 - SATA 10 were all "off" and said "no device found" or something. so i turned SATA3 to "on". When i rebooted it immediately said "SATA3 device not found, F1 to continue, F2 to enter setup. If i continued and went to the grub menu and of course the same error 21.
But! Then i turned SATA3 off and tried turning SATA4 on, and hooray! Everything worked fine. So definitely make sure to fool around in the bios and try turning all the device on one by one. Hooray Ubuntu! -- Grub - Error 21 returned https://bugs.launchpad.net/bugs/8978 You received this bug notification because you are a member of Ubuntu Bugs, which is a direct subscriber. -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
