Registry key gone missing?

[ChronicleMe]

My Samsung SSD software (Magician) is now indicating that it needs to be in AHCI mode for best performance. Well, I had it in AHCI mode and somehow it switched back to IDE on it's own.. I went in to Regedit to check the values on HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\msahci and noticed that "msahci" is no longer in there.

How can I fix this and what could have caused it to be removed?

[Title shortened by moderator as it was way,way too long & uneccessary]

 

[ChronicleMe]

Can the moderator suggest a solution too?

 

[ChronicleMe]

Any help please? I realize that windows 10 uses storahci but I still can't get it to work in ahci mode... Very frustrated