1.    15 Nov 2015 #1
    Join Date : Nov 2015
    Apple Valley, CA, USA
    Posts : 6
    Windows 7 Ultimate 64 bit & Windows 10 Pro x64

    Can I Dual Boot After The Fact?

    If anyone thinks they are important, here are the specs for my machine. Skip them if you want. I have never purchased a computer built by someone else. They always seemed to be clunky and they put in what they want to sell you. I just like my builds much better than someone elseís.
    P/S: Antec Edge 650 (new as of a month ago)
    Mainboard: Intel DP67BG
    Processor: Intel i5 Quad Core 2320 3.0 Ghz
    Memory: Kingston DDR3 Ė 16 Gb
    Graphics: NVIDIA GeForce GT 730
    Hard Discs:
    Drive C: Western Digital 650 Gb 7200
    Drive E: Western Digital 2 Tb 7200
    Drive G: Seagate 150 Gb
    O/S: Windows 7 Ultimate x64
    Of course various peripherals that Iím sure are not germane to my post

    Okay, here is a sort of different W10 story in that it installed very smoothly and even ran very nicely (if you like that kind of interface) but I didnít want to replace my O/S. I just wanted to have 10 so I can play around with it before it gets to the point that itís the only thing available at which time Iíll have to switch.

    I really love my 7 x64. It is by far the most stable operating system Iíve ever used and I go back to before Windows existed. Bought Windows 10 Pro and decided to do a clean install on my back-up Seagate that normally just sits there doing nothing. (I do backup my data but keep everything on the 2 Tb drive.)

    So I unplugged both W/D hard discs and booted via the Windows 10 Pro DVD. As I said, it went very smoothly and I opened the hood and trunk and nosed around a bit, took it for some very easy road tests and decided to put it away for the day. I booted down, plugged the other two drives back in and waited for the fireworks to begin. I knew the BIOS was going to shit an IC because my C drive has always been my boot drive and for the O/S and not much else. I like to keep it as clean as possible. But I also know that I just finished installing Windows 10 on a freshly formatted HDD. So I knew a conundrum would take place and it did.

    I got a black screen with the message that my Windows system has had some files replaced or some non-descript hardware possibly was changed which rendered the boot process broken.

    Not a problem since I did not intend to be working on 10 for some time and I know how to revive 7 Ultimate since I tear it up a lot and Iím always pushing the limit on what itís made of. Just to make sure I got back to my regular work soon enough, I unplugged the G drive which is now the Windows 10 drive and kept my two W/D drives plugged in, and launched right into my desktop.

    I guess I said all that to say all thisÖand maybe I will have to clean and reinstall 10 but Iíd like to find out if I can dual boot at this stage. Mind you, when I installed 10, my machine knew nothing of another O/S or other drives, applications etc. So is it possible to dual boot after both O/S have been installed on separate drives?

    I am very hesitant to install 10 with my other two drives still connected because about a year ago when I put the 2 Tb drive in, the boot files were scattered over two discs which made it hard to get it back to all on my C drive. Long story. I got very acquainted with the BCD at that time (thank you 7 forums and their members) and got it straightened out, but donít want to mow that yard again.
    Any advice or speculation would be appreciated.
    Sorry for the length of the post. Iíve never been accused of being succinct.
      My System SpecsSystem Spec

  2.    15 Nov 2015 #2
    Join Date : Sep 2015
    Posts : 2,188
    Windows 10 Pro 64-bit 1607 (AE build 14393.321)

    You can connect your Windows 10 disk again and then enter BIOS and make sure your Windows 7 disk is first in hard disk priority, BOOT section. If your Windows 7 disk is first in the list, your system will try to boot from it first and you should see the Windows 7 desktop without having to do anything on your part. Then you have to use EasyBCD (so as not to mess with bcdedit) and add a boot entry for Windows 10. In theory this is possible, although I have read in another post that you can only add a boot entry in Windows 10 for 7 not in 7 for 10. However, I would try it. If this is not possible, then you have to change the hard disk priority to make Windows 10 first, boot into Windows 10 and use EasyBCD to add an entry for Windows 7. You can also make Windows 7 default. Either way, you should be able to dual-boot Windows 7 and 10 by simply setting the right hard disk priority and adding a new boot entry in Windows Boot Loader.
      My System SpecsSystem Spec

  3.    15 Nov 2015 #3
    Join Date : Nov 2015
    Apple Valley, CA, USA
    Posts : 6
    Windows 7 Ultimate 64 bit & Windows 10 Pro x64

    That may work because my BIOS allows for ordering the hard discs aside from boot order. I'll try that in the morning and post back. I use EasyBCD anyway. Thanks, I'll let you know

    Okay changed the hard disc order so that my C drive boots first. Then when I booted the machine, just after the POST I got a message saying some files needed to be repaired. I viewed the information and it was changed to dual boot automatically. The only thing I'll change is that it put W10 as priority so I'll go into the BCD and change it to 7 priority.
    Thank you for the information. All is good again.
    Last edited by Irishman331; 15 Nov 2015 at 11:23.
      My System SpecsSystem Spec


Similar Threads
Thread Forum
Solved Reinstalling Windows 7 on 7/10 dual boot breaks dual boot
I installed the 10 tech preview along side my win 7 ultimate, I reinstalled, the Windows 7 side of the HDD because after however many years the OS had a LOT of clutter, and even though windows update was a nightmare I finally got all the updates...
Installation and Setup
Ubuntu Boot option still available in UEFI BIOS after Dual Boot
Recently I played around with dual booting Linux Mint on my system. I decided that I would delete it for the present as I have other things to focus on. However, after deleting partitions and fixing my MBR to only boot windows my UEFI BIOS still...
General Support
Solved No Windows Boot Manager on dual boot system (7 & 10)
Today I installed Windows 10 on my machine (ASUS N55SF laptop) for the first time on a separate hard drive. Now I have Windows 7 on my main hard drive and Windows 10 on my new drive (the latter being an SSD one). After installing Windows 10, I got a...
General Support
What is my upgrade path from dual boot back to single boot
My laptop has dual boot - Windows 7 and Windows 10. My Win7 environment is my main working environment with lots of programs installed and important files. I installed the Win10 environnment just to play around with 10 during the technical...
Installation and Setup
Solved No boot menu on dual boot WIn8.1↔10
HIYAS I have installed Win10 on secondary partition while keeping Windows 8.1 as primary. Everything went fine, after few reboots Win 10 was ready to use. After setting up things I rebooted, In boot manager I have two entries - Windows 10 as...
Installation and Setup
Our Sites
Site Links
About Us
Windows 10 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 10" and related materials are trademarks of Microsoft Corp.

© Designer Media Ltd
All times are GMT -5. The time now is 21:25.
Find Us
Twitter Facebook Google+

Windows 10 Forums