[SOLVED] Windows 10 fresh reinstall won't boot without install media

lachallenger

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I recently installed a fresh copy of Windows 10 Pro in place of my former installation of Windows 7 - I did not upgrade, but cleared my system drive and installed clean.

Since doing this, the hard drive will not boot alone. There are three physical drives, the system drive, one drive for programs and one drive for documents and such.

The main difference is that the programs drive is larger and appears to be GPT formatted.

I have tried using three bootrec commands, fixmbr, fixboot and rebuildbcd, the latter with some instructions to backup the old BCD before rebuilding. I may try the manual efi folder install method I've seen from Easy Tech Tutorials, but right now, I am just utterly confused as to what my next move should be.

If further information is needed, please ask.
 
Solution
Okay, my bad I forgot GPT partitions will not show up on the Disk Manager screen.

which disk manager? DIsk management in windows most definitely shows GPT partitions. It won't flag them as such unless you look in properties/volumes of the disk, or the disk itself has an EFI partition.

The image the op attached wasn't working for me so I removed it.

BTW, is the Disc in the DVD player your install media? If so don't worry about the GPT partitioning as a MS install media works with either GPT or mbr, it just must be GPT to be compatible with GPT.

Close, the format of the DVD should be FAT32 or NTFS, as that is file system. Unless the installer is created by Rufus, it is likely to recognise Legacy or UEFI , as...
It sounds like when you installed Win10, it installed itself spread out over 2 drives, This is why you should always disconnect all drives except the target drive for the OS. If possible show a screen shot of your Disk Manager. The best fix is to disconnect your other drives and do a clean install of Windows 10 https://forums.tomshardware.com/faq/how-to-do-a-clean-installation-of-windows-10.3170366/ Then go back and delete the partition windows 10 placed on other drive.
 

lachallenger

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I'm not sure that was it - when I was on Windows 7, I did notice that there seemed to be another partition that wasn't on the main C drive - I removed it, since I had one installed right where it should be on the primary system drive. I am using three SATA hard drives, for what it is worth - is there some weirdness about load order with them? Do I need to explicitly have the system drive plugged in first? Better question - can I change which is plugged in where, without needing to reinstall Windows 10? (Image of Drive Manager incl)
 
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I don't think there is a fix, beyond disconnecting your other drives and doing a clean install. Looking at your OS drive, the "WIN C:" is more often seen with Windows 7, not Windows 10, which simply shows "C:". so it looks like the two have commingled, which can explain the problem with booting. BTW, is the Disc in the DVD player your install media? If so don't worry about the GPT partitioning as a MS install media works with either GPT or mbr, it just must be GPT to be compatible with GPT.
 
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lachallenger

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How could they have commingled that way o_O - I named the main Windows partition myself? And yes, the disc is the installation media, in the DVD drive. I completely cleared the hard drive when I first set up Windows 10, using Diskpart - I removed all partitions and volumes in one go, as part of installation. The Reserved spot was set up during the install as well. Gods - would I really have to disconnect the other two hard drives just so I could reinstall Windows? Even more confused now.
 
Yes, Windows install media has a bad habit of not properly installing with other hdd present, it's probable there is boot information on another drive.

Also, what does this statement mean "The main difference is that the programs drive is larger and appears to be GPT formatted", mean. The only GPT formatted drive is the Media install DVD in the F: drive. Confirm you can only boot with the install media DVD in the DVD palyer?
 

lachallenger

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Looking at them from Diskpart - the drive I predominantly use for program files is the largest and has the GPT flag on it.

Nuts. I wish I had known that I needed to disconnect the other drives when I first did the install - I've already had to start reinstalling things
 
How could they have commingled that way
The windows installation looks at your bios to determine which hdd the system starts up from and installs it's bootfiles on that drive even if you are installing windows on a different hdd.
Makes sense doesn't it?! You want your OS to be able to start.

You can use the free community version of easyBCD (or windows's own BCD commands from cmd) to make your OS drive bootable and create an BCD store on the OS drive so it will boot from itself.
 

Colif

Win 11 Master
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Okay, my bad I forgot GPT partitions will not show up on the Disk Manager screen.

which disk manager? DIsk management in windows most definitely shows GPT partitions. It won't flag them as such unless you look in properties/volumes of the disk, or the disk itself has an EFI partition.

The image the op attached wasn't working for me so I removed it.

BTW, is the Disc in the DVD player your install media? If so don't worry about the GPT partitioning as a MS install media works with either GPT or mbr, it just must be GPT to be compatible with GPT.

Close, the format of the DVD should be FAT32 or NTFS, as that is file system. Unless the installer is created by Rufus, it is likely to recognise Legacy or UEFI , as a DVD created by Media creation tool can boot off either. It is the legacy/UEFI flag that tells the OS if it can install as GPT or not.


If you clean install win 10, do it with only 1 driver attached as it stops it sharing itself around on other drives it finds free space on.
 
Solution
I did not say Disk Management would not show GPT partitions, I said GPT partitions will not show up on the Disk Manager screen, meaning the opening screen the OP had posted; you know the, "The image the op attached wasn't working for me so I removed it." I was going to go back and change the GPT statement about the DVD install media, ( I was thinking USB at the time) so thank you for correcting it.