Windows 10: 1rst Try at Clean Install of 10122 breaks bootloader of Win 7

Have been dual booting Win 7 and Win 10 previews on two Samsung ssd's. I've had no problem with updating each build then extracting the Iso with ESD to Iso then doing a clean install until the switch from 10074 to 10122.

Let it update on fast ring - no problems.
Extracted Iso with ESD then did clean install.
Would boot to Win 10 but the Win 7 boot disappeared.
Tried everything - restoring image with Acronis, Win 7 repair disk etc. Nothing worked.
Reloaded Win 7 from scratch then tried again clean install of Win 7 and worked perfectly.

Luckily all my files are backed up on an external drive.
Any thoughts?
Jim

:)

 

Adding Windows 10 dual-boot (clean install) to a Windows 7 Laptop.

Now that we have the ability to clean install 10 onto a pre-existing 7 machine, and then activate using the pre-existing 7 key...

1. Created a 200GB partition for 10.

2. Booted from USB 10 installer (created today, so latest version).

3. Installed 10 into said 200GB partition with no reported errors.

4. Installer first reboot re-loaded the installer, so removed and rebooted. You'd think they would do something about this, but I'm not holding my breath. Also few walkthrus mention this fact.

5. Boots Windows 7 original bootloader with no sign of the 10 install, so unable to continue on with the setup.

6. Booted into 7 and I can see the installed 10 partition (with no drive letter obviously). Assigned a drive letter and explorer shows Win 10 files are present, and what looks like a bootloader.

According to various sources a Win 10 install will lay down its own bootloader and provide a dual-boot to the pre-existing o/s, in this case Win 7.

As a quick and dirty I used EasyBCD to create a third entry to 10 inside the 7 bootloader, but it throws an error when trying to use that option, something about not being able to verify the o/s.

It should be noted this is an MBR arrangement, a Dell machine, with a separate 20GB OEM recovery partition containing the Win 7 bootloader. Partition Wizard shows the 10 partition status as "None". I would have expected it to be at least "System"?!?

Any "intelligent" ideas much appreciated.

EDIT: this problem has been solved on the TenForums:

Ten Forums Solution

 

download here - can upgrade 10122 -> 10162... NOT fresh install?

How upgrade a Vmware Player 7 VM: win 10 pro preview 10122 -to-> 10162...?

Needed really boot from DVD?

 

Install EasyBCD or VisualBCD, reintall legacy loader and recreate the entry for Windows 7. This should work!

*Smile

 

Did you disconnect the Win 7 drive prior to the Win 10 install? The first time I ever tried a dual boot I forgot to disconnect the prior drive and it messed it up. Since I have always disconnected the Win 7 SSD and did a clean install of Win 10 on the other SSD. Never had issues again.

 

I will keep this in mind. I'm not the best at this. I will need to explore EasyBCD and see if I can figure out how to install the legacy loader.

Stealth - if I disconnect the Win 7 drive and Install 10 on the other will I get the dual boot screen when booting? I've been wondering about this.

It was time for a clean install of 7 anyway.
Thanks
Jim

 

Yes you should. I turned the computer off, ejected the Win 7 SSD (I installed front case drives just for this) did a normal clean install of Win 10 on the other SSD. Once it was totally done, I turned the computer off again, inserted the other SSD and started the computer again and it booted to the dual boot selection screen.