Nog even een aanvulling. Mijn probleem blijkt een jaar geleden gerapporteerde bug in Grub (maar blijkbaar niet opgelost).
GRUB recognizes defunct LDM headers
1. Ubuntu
2. “grub2” package
3. Bugs
4. Bug #1061255
Reported by Joe Sweeney on 2012-10-03
96
This bug affects 18 people
Affects
Status
Importance
Assigned to
Milestone
grub2 (Ubuntu)
Phillip Susi
Quantal
Phillip Susi
Also affects project (?) Also affects distribution Nominate for series
Bug Description
[Impact]
Grub can no longer boot Windows
[Test Case]
Use Windows to format a dynamic disk. Use fdisk to repartition the disk as a regular MBR disk. os-prober still recognizes the defunct ldm partition table with the Windows partition in it.
[Regression Potential]
Previously grub had no support for ldm, so the worst case is that it goes back to not recognizing ldm, as opposed to the goal of this patch of only recognizing *valid* ldm.
.
GRUB recognizes stale LDM headers left on the disk after reformatting without LDM. This causes grub to complain either that embedding is not possible, and/or to incorrectly use the ldm partition module instead of msdos.
- This bug affect GRUB2.00 (default bootloader of Ubuntu12.10).
- This bug completely breaks access to any operating system, either when installing a fresh 12.10, or when upgrading from 12.04 to 12.10.
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WORKAROUND1 (when GRUB appears, but the Windows entry fails and shows a "A disk Error Occurred" error):
see Comment #44 below (
https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1061255/comments/44 )
WORKAROUND2:
see Comment #26 below (
https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1061255/comments/26 )
WORKAROUND3:
Use Boot-Repair (
https://help.ubuntu.com/community/Boot-Repair ) from liveCD to replace GRUB2 by GRUB Legacy: run Boot-Repair --> Advanced options --> GRUB options tab --> tick "GRUB Legacy" --> Apply
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