It may happen that you discover that your preinstalled Windows isn’t set to use AHCI on hard disks or SDDs.
If you simply commute the BIOS settings, the OS will not be able to be loaded anymore.
Looking for solutions, I found the following ones:
Windows 10
According to this page (at http://www.tenforums.com), mainly you have to:
- setup windows to run in safe mode on the next reboot
- update the BIOS setting
- restore windows to normal mode, and reboot again.
From a Command Prompt with Admin privileges:
- to set the safe mode on the next boot, you have to type the following:
bcdedit /set {current} safeboot minimal
to set back the normal mode on the next boot:
bcdedit /deletevalue {current} safeboot
Windows 10 + 8.x
From this page (at http://www.tenforums.com), the approach is a little more complex.
We have to update the following values in the registry as follows:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ + iaStorAV\StartOverride key: 0 + iaStorV key: Start + storahci key: Start + storahci\StartOverride key: 0
Update the values above to 0.
Reboot, update BIOS configuration, and follow Windows instructions.
Windows 7 + Vista
From this page (at http://www.sevenforums.com), the approach is similar to the previous one but on different registry keys.
We have to update the following values in the registry as follows:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ + msahci value: Start + iaStorV value: Start
Update the values above to 0.
Reboot, update BIOS configuration, and follow Windows instructions.