A lot of users have been messing around with AHCI after installing Windows 8. Some users have reported that they can’t get Windows 8 to install without disabling AHCI. Here at iTD, we haven’t faced any such issue though we have a quick fix for such a situation. It’s very easy to enable AHCI after installing Windows, although it isn’t visible to users as a simple switch on/off option.
What is AHCI and why should you care?
AHCI ( Advanced Host Controller Interface ) offers native command queuing and hot-plugging through SATA host controllers (Serial-ATA) for hard drives. In simpler terms, there’s no reason you shouldn’t use it.
Updated method
A lot of feedback has been given with our visitors sharing different levels of success in the below method. The method had worked for me and some users but an easier version for Windows 8 is below which seems to work for everyone. (Thanks Marcel!)
- In search, write cmd, right click it and run it in administrator mode.
- Type the following command to enable SafeMode boot:
bcdedit /set {current} safeboot minimal - Restart the computer and boot to the system BIOS. This is normally done by pressing the delete key during system boot.
- Update the ATA Drive setting in the BIOS from ATA Mode to AHCI Mode. Save the setting and restart your computer to boot into Windows.
- Windows will boot in SafeMode as per step 2.
- Open the command prompt again by following step 1 and run the following command to remove the SafeMode boot option:
bcdedit /deletevalue {current} safeboot - Restart the computer and boot normally.
While the below instructions don’t work for everyone, I’ll leave them here for those who found it useful.
So, how do you enable it? Do you have to reinstall Windows 8 again?
No. You can enable it without losing any data.
Enabling AHCI in Windows 8 requires going through the registry ( yes, it’s still there! ) but it’s slightly different than how it was done in Windows Vista and Windows 7. You still have to modify a registry key but the key is different now. Follow the guide below to enable AHCI in but make sure that you’ve backed up your data as well as registry, just in case.
- Exit all applications
- Go to the start screen and type in Regedit.
- If you see the UAC (User Account Control) dialogue box, just click continue.
- Locate the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\storahci\
- Locate the Error Control entry which should have a value of 3. Right-click on the entry name, select Modify, change the value from 3 to 0 and click OK.
- Open the StartOverride folder and locate an entry named 0 with a value of 3. Change the value to 0 by following the procedure in step 5.
- Restart and enable AHCI in your system BIOS
Quick Alternate Method
If you don’t feel safe playing with your registry like I don’t with a neighbor’s dog ( except that I can handle a messed up registry but not a messed up dog ), I suggest you download the registry file I’ve uploaded here. Just extract the .reg extension file from the compressed folder and run it and restart your computer. Do the obligatory AHCI switch on from your system BIOS and you’re good to go.
Disclaimer
As usual, the author and owner of this website aren’t liable for any loss caused by the above guide. If your neighbor’s dog bites you, your computer blows up or hard drive refuses to work, I hereby take no liability. Of course, if you say please, I’ll be more than happy to help. :)
Update: updated with some input from Lyrad Kcirhor, thanks!
Update for Windows 10 users: As commented below by gapooter, this method also works if you want to enable AHCI in Windows 10. Just follow the 2nd method of editing the registry and ensure you make a backup before proceeding.
Thanks man! I was 5 minutes away from a full re-install.
Many many thanks! You saved my day in less than 3 minutes!
Looks good !
Noticed the storahci key is deeper modified later (and cannot be manually reverted; who cares ??…)
Hi, I tried this solution, but 1) AHCI was already selected in my BIOS and 2) when I checked the registry entries after rebooting, “0” in the StartOverride folder had reverted to a value of 3.
My computer also boots quite strangely. When I go to Desktop, it takes a few seconds for all of the icons to load. The programs also take some time loading in the tray (I don’t recall this problem with Win7. My computer is quite fast). Could it be due to the fact that I upgraded instead of doing a clean install?
Worked perfectly – mega thanks as the thought of having to do a fresh install having only just reinstalled os and fully updated everything plus downloading all my games was one i was not looking forward to ! This took all of five mins and job done ….wooo hooo :)
Your registry key file ruined my Windows 8. It made my computer ran in Automatic Repair loop. When I disabled automatic repair mode. I found out that your key cause Windows to load msahci.sys which is not available in windows 8. Please remove the registry key file you provided.
I had to load registry hive from recovery console and restore original storahci key.
Apologies for the inconvenience. I had written this based on what worked fine for me but I’ll modify it.
Same thing too. It was too easy to download. Couldn’t do it myself. Now, I have to reinstall windows. Maybe, hopefully I can fix it. Any idea how through windows recovery?
Dude can you please post the steps to disable the auto repair and stuff
Same problem here. I have no idea what to do now. I forgot to make a backup and now I may have to reinstall Windows from scratch. This sucks.
Same thing happened to me.. trying to fix it now
Ugh. Stuck in RAID mode. Nothing I try works. Do you think repairing windows while in AHCI mode would work?
Hello, Where can I find “StartOverride folder” ??
inside the “Services\storahci\” folder!
Oh my gawd thank you man! :D
Did not work for me. Got exactly the same error when starting up as I got when I tried enabling AHCI before modifying the registry key: boot device not available. Had to go back to “compatibility mode” in BIOS to start Windows successfully.
Also saved my day. Just wanted to do a refresh installation. Thanks.
Thank you,
Thank you very much for the information you provided. It completely resolved the same issue, I too have been having.
hi
thanks for guidance
i added this registry and then restarted and enabled ahci
but windows 8 couldn’t start
so i disabled ahci and restart pc again
but windows couldn’t start again
and then system restore opened and i restored my windows 8 finally windows started
what should i do ?
Hey I just wanted to confirm that the manual editing of key registries worked for me! Thanks man
I could not get this to work by default and I had done it previously in Windows 7. The answer and I think I should share for people who still have problems is outlined in MS KB article.
YOU SHOULD DO IT IN SAFE MODE
http://support.microsoft.com/kb/2751461
I try with manual form and with automatic form and Didn`t worked, when its loading SO give an error (Blue screen with :( smile) and restart. I have Samsung 840 ssd.
Thanks – I’m glad it’s working for some of you guys. I tried it, and was unsuccessful. I did a System Restore to earlier today (unfortunately, undoing a few hours of installations).
I have an HP HPE-510t with a Pegatron Cleveland-GL6 motherboard (Intel H67/Core i7-2600), with a RAID 0 (stripe) HDD array for data, and a Samsung 840 PRO 128 GB SSD with a clean install of Windows 8 Pro. RAID was the setup when I installed Windows 8. I installed the latest Intel RST driver package (1030).
I blame HP and their lack of support for PCs over 2 yrs old. For my Nov. 2010 machine: No BIOS update for Windows 8, no guide for Windows 8 OS upgrade or clean install methods, and no help enabling AHCI mode, or documenting UEFI in any shape or form. No GPT support, though my hardware’s capable. Same thing happened with my dv2000t laptop and Windows 7. Bye, HP.
This tip worked perfectly for me last time.
Today, my AHCI has been switched off (i don’t know why) and i’ve tried this tip again but this time, that don’t work. There is a BSOD on each boot when the AHCI is on in the BIOS.
DO NOT use the reg file posted! The instructions above are mostly correct but the file is not – if you did see the instructions to boot from CD/DVD and repair by setting all of the values below plus in storahci set the ImagePatch value to:
System32\drivers\storahci.sys
You only need to change these values to activate AHCI in Win 8:-
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\storahci:
Start = 0 (default = 3)
Error Control = 0 (default = 3)
Then in the StartOverride sub-key set:
0 = 0 (default = 3)
The StartOverride doesn’t show in my loaded registry when Win 8 is normally booted so I couldn’t do this in advance. If you find the same then you might need to do the following – which is also the same way for any of you above to fix without a reinstall:-
Boot from a Win 8 CD/DVD of the same architecture (32 or 64-bit), select Repair then in the advanced tools open the command prompt.
Type regedt32 and press Enter.
Highlight HKEY_LOCAL_MACHINE, then File>Load Hive>[choose volume with Windows installed]:\Windows\System32\Config\SYSTEM>Open>Key Name = Restored_HKLM>OK.
Expand Restored_HKLM\ControlSet001\services\storahci.
Update the key values as required from above.
Close (updated values are saved as soon as you hit OK), type Exit and press Enter at the command line, shut down, boot up and enjoy Windows 8 with AHCI.
Post back if this doesn’t work for anyone.
Also see here if you’re trying with an earlier version of Windows – I fully understand how incredibly frustrating a non-booting Windows is!
http://social.technet.microsoft.com/Forums/windowsserver/en-US/b4d45d9d-4c90-4ab0-ae38-f1257ce9c608/windows-7-server-2008-r2-bare-metal-restore-0x0000007b-stop-error
Chris
Just got a sweet Samsung 840pro 512GB SSD and the Samsung Magician Software says it isn’t running optimally because of AHCI.
I’m on a Dell Latitude e6520 – and I tried everything above and then went into Bios and changed to AHCI but it doesn’t find my drive anymore and won’t boot.
It was previously on RAID (something to do with Intel rapid store tech?) if that makes any difference
IrishChris,
Me again – Also I had run the file previously and I just noticed your comment about “ImagePatch”. Presuming you mean “ImagePath”… mine says
\SystemRoot\system32\DRIVERS\msahci.sys
should I alter as per your recommendations?
Hi Steve,
Oops, sorry yes ImagePath!
2 Qs:
Assuming your laptop has Windows 8 installed (sorry, just checking)? If Win 7 or less leave it as you’ve quoted, otherwise yes change it to the path mentioned as msahci.sys doesn’t exist anymore in Win 8. (besides, it’s a safe change as easy to change back)
I take it you mean it said RAID in the BIOS and which has been changed to AHCI –
how many drives are installed or were installed when it was on RAID?
Cheers,
Chris
I’d only use this as a last resort but it doesn’t do any harm other than a few milliseconds at boot to enable (set Start = 0) all of these drivers in ControlSet001\services:
aliide, amdide, amdsata, atapi, cmdide, iastorv, intelide, msahci/storahci, nvstor, nvraid, pciide, viaide, LSI_SAS, LSI_SAS2
I used the second part and modified my registry regedit changed the 2 values from 3 to 0, then rebooted in bios, switched to ahci, but now my PC is bricked. It will only boot in a special mode called efi shell version 2.31 (my motherboard is a MSI 970a-g43). If I switch SATA mode back to IDE it boots to the same screen. I’m stuck don’t know what to write in this efi boot to make it work. Seems to be trying to map something but stops and wants me to enter something. Help??