[SOLVED] Unable to boot from M.2 after wiping an old HDD

[bphudson93]

I had an old busted PC with a still-functioning 1TB HDD running Windows 10 Pro. I installed the old HDD into a new PC build in December so that I could salvage the games/music/docs/etc. from it and then wipe the HDD for a backup drive. For the new PC, though, I installed Windows 10 Pro on a brand new 1TB M.2 NVMe drive (Intel 660p Series, if it matters). When I would start the new PC, I would be given the option of booting Windows from either disk. I've been doing that for about six months, too lazy to do the backup thing.

I stopped being lazy today. I finally got around to moving everything I wanted from the HDD to the M.2. I deleted the HDD's partitions and reformatted the drive to get rid of its Windows installation and all of the applications taking up most of its space.

Apparently this was a huge mistake. Hubris. I have been unable to boot from the M.2 drive, despite it being first in the boot order.

From having read around some while trying to fix this problem, I'm pretty sure the issue is that I had the HDD (with its old Windows 10 install) connected when I installed Windows 10 on the brand new M.2 drive. Apparently the M.2 doesn't get all the good boot stuff in that install situation, for some counter-intuitive reason. Who am I to quibble with the way Microsoft designs their installation experiences, I guess?

Anyway, in order to make my PC at all usable again, I reinstalled Windows 10 Pro on the HDD. Now, however, I'm not given the option to boot from the M.2 drive. I'm stuck using the fresh installation on my HDD.

Is there any way, from here, to repair the Windows 10 Pro installation on my M.2 to allow me to boot from that disk instead of this old HDD? Or do I have to move everything from the M.2 back to the HDD, reformat the M.2, disconnect the HDD, reinstall Windows on the M.2, reconnect the HDD, move everything back to the M.2 again, and then finally wipe the HDD clean like I originally intended?

[I'm trying to be helpful and post an image of my Disk Management screen, but "Something went wrong" with the Insert Image function. Here's a link.]

Any advice, y’all? Your expertise is very much appreciated.

 

[Mooons]

Can you see the M.2 drive if you go into the windows installation menu after post?

 

[bphudson93]

Can you see the M.2 drive if you go into the windows installation menu after post?

Yes. Here's what the M.2 drive partitions look like in the Windows install menu.

Name	Total Size	Free Space	Type
Drive 1 Partition 1	16.0 MB	16.0 MB	MSR (Reserved)
Drive 1 Partition 2	953.9 GB	36.2 GB	Primary

 

[Mooons]

Yes. Here's what the M.2 drive partitions look like in the Windows install menu.

If you select and delete both Drive 1 Partitions then it will let you continue and you'll be able to install windows 10 on that drive from the installation.

 

[bphudson93]

Won't that delete everything currently on the M.2? Does that mean there's no way to fix the current installation on the M.2 so I don't have to move everything over to the HDD and then back?

 

[Mooons]

Won't that delete everything currently on the M.2?

My bad, yes.

I would just move everything over again and then disconnect the HDD when you install windows on the M.2 that way nothing can go wrong.

It'll be worth the work because the speed/boot times are wayyyy better than the HDD.

 

[bphudson93]

My bad, yes.

I would just move everything over again and then disconnect the HDD when you install windows on the M.2 that way nothing can go wrong.

It'll be worth the work because the speed/boot times are wayyyy better than the HDD.

Oh, for sure. I know it's definitely worth it to have the OS on the M.2. I've been using it for the past six months before I wiped the HDD today.

It's really frustrating that Windows gave no indication that it wasn't doing a full install on the M.2--that its bootability was enslaved to the HDD's install. Live and learn, I guess.

Well, I guess it's time to transfer like 900 GB worth of stuff from drive to drive two times...
Thanks for the help, though.

 

[Mooons]

I guess it's time to transfer like 900 GB worth of stuff

0_0

 

[The_Prophecy]

This is why the recommendation here among the more veteran volunteers is to ALWAYS remove every other drive in a system when setting up Windows. Newer versions have definitely gotten better about not dropping the bootloader on another volume in the system, but it still happens occasionally.

I always hate to see people having to deal with the fallout and basically learn this the hard way, but as Jay has been saying, that really is the best way to get this all set up properly.

Once you get everything transferred over to the hard drive, disconnect it and and then wipe the M.2 as the only connected disk, and the Win 10 installer will set up the bootloader and all the other partitions it needs on the M.2 and only on the M.2. Once your install is finished, reconnect the HDD, boot up again and you can start moving everything you need back over.

 

[bphudson93]

I'm usually one to learn as much as possible about my PC-building stuff before I jump in, but it never even occurred to me that the Windows install was something I could screw up so spectacularly.

 

[The_Prophecy]

Well I'm not sure that was exactly your fault either. Microsoft has a tendency to make any new bootloaders being installed look for any existing ones present in the system and append to them, even if they exist on a volume that is not the target for the new install being done. This is kind of a compatibility thing, due to how many people used to set up multiple partitions on their machines and install multiple operating systems (XP on one, and 7 on the other for example) to arrange a dual boot environment.

These days however, that kind of setup is becoming less and less relevant or necessary.