[WIN8] Installing Windows 8 Upgrade on fresh, empty drive (reg key change)

ir0nw0lf

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Today, I have read around the internet about eleventy billion questions/answers about installing the Windows 8 Upgrade via various scenarios, the one that seems to be baffling people is this one:

Can you install the Upgrade on a fresh, completely empty hard drive, one with no OS already on it and no other drives with an OS hooked up?

This is *not* asking if you can do a "clean" install on a machine with an existing OS on it. This is asking basically, if I build a new box with new drive and no other OS on it, installing a larger replacement drive and/or SSD drive, etc.

I asked this question over at Neowin forums and wow, the answers are literally all over the universe. From what I can gather, initially the answer is NO, you can't. Users have installed it but it won't activate, the error message is about installing the OS with no previous OS being seen.

However, someone posted a registry key that needs to be changed before activation, very similar to the Windows 7 double-install method. The registry key is:

Code:
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Setup\OOBE]
"MediaBootInstall"=dword:00000000
According to the user who posted that, using the upgrade download (maybe even the upgrade boxed copy) with the upgrade key results in the above key being 1 not 0. It will not activate as such. Changing the key to 0 will allow for successful activation. Seems the TechNET/MSDN version when installed sets this key to 0 out of the box. Some have also said the TechNET/MSDN .ISO will activate fine with the upgrade keys.

I have not personally tried this [yet] and can't vouch for the accuracy of this. Would love to know if anyone here tries this and it works/fixes their problem(s).

EDIT: MODS, if this violates any rules, please do what you need to do.
 
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The box version of 8 is def worth the extra $20 bucks. It is a full retail version...not bad at all.
 
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I didn't find this thread until I tried activating with the dword set to the default value of 1. I then went back and changed to 0, still no joy.
I'm assuming for this to work it has to be changed PRIOR to activation. I'll probably go back and format again, make sure that Win8 isn't set to automatically activate, change the value to 0 then manually activate.

If anyone wants to test this out please report back.
 
I tried activating with the dword set to the default value of 1. I then went back and changed to 0, still no joy.

Here's the missing link:

1. Open elevated command prompt (Right click -> Run As Administrator)
2. Type slmgr -rearm <enter>
3. Reboot

Voila, should be activated after reboot. If not, re-enter key and should activate.
 
Here's the missing link:

1. Open elevated command prompt (Right click -> Run As Administrator)
2. Type slmgr -rearm <enter>
3. Reboot

Voila, should be activated after reboot. If not, re-enter key and should activate.


holy hell....5000 Internets to you my friend....IT WORKED
 
Here's the missing link:

1. Open elevated command prompt (Right click -> Run As Administrator)
2. Type slmgr -rearm <enter>
3. Reboot

Voila, should be activated after reboot. If not, re-enter key and should activate.

Bravo for that additional info!
 
I bought the $39.99 version. Had Windows 8 Beta on the SSD. Downloaded and made Windows 8 USB install stick. Booted with the USB stick, when it asked what drive I wanted to install on I delete everything on the SSD and selected it. During install it asked for my product key and I entered it. Once finished I went to system and it said it was already activated so I don't know if it noticed the Win 8 beta on the drive before I deleted the partitions but it never asked me for anything else.

So I had no problems doing a clean install with the upgrade version.
 
Here's the missing link:

1. Open elevated command prompt (Right click -> Run As Administrator)
2. Type slmgr -rearm <enter>
3. Reboot

Voila, should be activated after reboot. If not, re-enter key and should activate.

A million thank you's to you as well
 
Here's the missing link:

1. Open elevated command prompt (Right click -> Run As Administrator)
2. Type slmgr -rearm <enter>
3. Reboot

Voila, should be activated after reboot. If not, re-enter key and should activate.

Awesome, man! Thanks a lot!
 
I had no problems running the 39.99 version with a clean install (formated my ssd).
 
Ths is interesting I'm about to download the upgrade for my home desktop and then do a clean install on a fresh ssd via the upgrade/clean install. Please post the issues anyone runs into :)
 
I thought you couldn't install Windows 8 without first activating it? I know in Windows 7 you could just skip the key and enter it later. So how do you set this registry key?

My interpretation is: You do have to enter the W8 key during setup and it lets you continue but fails to activate...and then it boots into the OS but is unactivated and gives you the 5 or whatever days to activate? Is that close?
 
I thought you couldn't install Windows 8 without first activating it? I know in Windows 7 you could just skip the key and enter it later. So how do you set this registry key?

My interpretation is: You do have to enter the W8 key during setup and it lets you continue but fails to activate...and then it boots into the OS but is unactivated and gives you the 5 or whatever days to activate? Is that close?

You can install without activating. Otherwise it would be impossible to install on offline PCs.
 
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I've installed upgrade on two PC's and activated without any issue. One was Vista base install off Win8 USB stick and other was barebones off USB Win8 stick. Both where technically upgrade keys/ Got lucky maybe?

I'll be picking up a couple more keys for VM's as I'm really liking windows 8, much to my surprise.
 
Here's the missing link:

1. Open elevated command prompt (Right click -> Run As Administrator)
2. Type slmgr -rearm <enter>
3. Reboot

Voila, should be activated after reboot. If not, re-enter key and should activate.
Thank you so much, worked perfect.
 
Thanks for this, gona try it.
But to clarify - you have go do both steps?
 
Thanks for this, gona try it.
But to clarify - you have go do both steps?

I've been meaning to do another install with the slmgr -rearm alone to see if the reg change is even required, but for now it will definitely work doing both steps, and the reg change alone didn't work for me, I had to do the slmgr -rearm in elevated cmdprompt to reset the activation and make it stick
 
Quite a timely thread. I just got my copy on Win 8 pro upgrade and new ssd in the mail today.
 
I got the boxed version from Office Depot for $39, went home, put a new drive in my laptop and did a full install on the fresh drive. Did the reg setting and no issues at all. Was very simple and very fast.

Not sure why anyone else has issues.
 
I bought the upgrade version during that promotion sale and had no problems installing it on my laptop with a fresh partition (no prior OS). No issues whatsoever, installed like a full version. I removed the partitions on my HP DV6 laptop so I could gain back the small space HP takes up for their software. Worked out great.
 
Going to an MicroCenter tomorrow and I was wondering about if this still worked and how well. I am about to build a new computer, probably tuesday/wednesday whenever the final parts arrive and I saw MC had Win 8 Upgdrade for $39. Thought this would be a great price if I could get it to work on my new build with the SSD I purchased. Doing the steps mentioned previously should work fine right? Or has this been patched?
 
Bought the license directly from Microsoft, downloaded it via the Upgrade Assistant tool, created a bootable USB, did a clean install and it worked fine, didn't have to do any registry edits or hacks, very pleased so far. This was also the upgrade version I bought as well.
 
Bought the license directly from Microsoft, downloaded it via the Upgrade Assistant tool, created a bootable USB, did a clean install and it worked fine, didn't have to do any registry edits or hacks, very pleased so far. This was also the upgrade version I bought as well.

That's not the same thing as installing on an empty drive...
 
Bought the license directly from Microsoft, downloaded it via the Upgrade Assistant tool, created a bootable USB, did a clean install and it worked fine, didn't have to do any registry edits or hacks, very pleased so far. This was also the upgrade version I bought as well.

Windows 8 detected a previous OS before it "cleaned" everything out for the Win 8 to take over....thats why it works fine....however if you took that same key and bought a brand new Samsung 840 PRO SSD...and tried the same thing....Windows would give you an error after it's done installing

Basically you need an MS operating system already on the drive in order for the upgrade Win8 to work properly....if you don't, then you will have to do the registry trick listed in the OP
 
Really? Thanks for the input guys, didn't even notice that myself. I thought you needed to boot into an existing version of Windows and install it from there.
 
Really? Thanks for the input guys, didn't even notice that myself. I thought you needed to boot into an existing version of Windows and install it from there.

No worries...I was confused myself, until I saw it with my own eyes....but basically Win 8 "upgrade disc" won't freak out as long as you have some kind of previous windows already on your drive...once it sees some kind of windows on there, it will proceed to clean install, and won't give you trouble...but if the drive is completely clean and new, it will hassle you, AFTER the installation is over...I believe Win VISTA and 7 upgrade discs, it will stop you BEFORE the installation, if it doesn't detect a previous version of windows already on the drive
 
Is this how it works in my case?

1. Buy the Win8 Upgrade and install over the Win7 Pro
2. Win8 gets messed up and need to do a fresh reinstall. Will the Win8 "upgrade" version work in this case?
 
Is this how it works in my case?

1. Buy the Win8 Upgrade and install over the Win7 Pro
2. Win8 gets messed up and need to do a fresh reinstall. Will the Win8 "upgrade" version work in this case?

Yes, as long as it detects an MS OS previously installed, Win8 will fresh install no problem....even if your previous OS got corrupted
 
Here's the missing link:

1. Open elevated command prompt (Right click -> Run As Administrator)
2. Type slmgr -rearm <enter>
3. Reboot

Voila, should be activated after reboot. If not, re-enter key and should activate.

This way works like a charm, tested with a promotional $14.99 upgrade key on a clean install with a new computer, no need to re-enter key after the rearm, on reboot it was already activated.
 
This helped with installing win8 after a changing drives and it wouldn't authenticate a second time.
 
When I did my install (upgrade) I just chose the "Dont keep anything" option and it did the job.
 
Just to be clear do you need to change the registry key to "0" first (as in the first post and if so what is the sequence?) or just do the three steps Odditory listed? so far this is what I have:

1. Change key from 1 to 0.
2. Open elevated command prompt
3. slmgr -rearm <enter>
4. Reboot (re-enter key if needed).

Is this correct?
 
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