Dummy with lack of dual boot (win 7/win 10) problem

I have a problem that, surprisingly, I haven’t been able to find a solution to by using search on here. I’ve also checked the common problems section, again with no joy. I will loosely detail my system, the events that lead to the problem and then the problem itself.

I own a 3 hard drive PC. Previously disk zero had Windows XP 32 bit installed, Disk one had Windows 7 32 bit installed and the final hard drive was a data disk shared by both XP and 7. It was a dual boot machine. Incidentally Windows 7 is the full retail version (as opposed to an OEM version which is what XP was).

As I haven’t used XP for quite some time, I decided to install Windows 10 64 bit home (full retail) on that drive to replace XP. My intention being to have a dual boot PC. Having previously set up a dual boot system, I did not anticipate any problems. However when I was installing Windows 10 I did not receive a query asking if I wanted to set up a dual boot system even though I had said I wanted to do a custom install.

So here is my problem. I now have a machine that boots straight to Windows 10. While it is nice to have a PC that gets to the desktop in under 30 seconds and the disk activity related to booting up ceases in less than two and a half minutes, I really need the ability to access Windows 7 as well as Windows 10.

What appears to have happened is that during the install process Windows 10 deleted the old BCD that was on disk 1 while leaving the rest of the contents of that drive intact (including all of Windows 7) and created a new BCD on disk zero.

Am I right in thinking that by editing the BCD on disk zero I would be able to regain a dual boot system again? If so, would someone be willing to give me very detailed instructions on how to go about this. I have downloaded and installed Visual BCD but I really have no idea how to use it. Is this the right tool for the job? Should I use something else?

Any help or advice will be gratefully received. Thank you in advance.

Welcome to the forum. For duel boot you always have to install the oldest o/s first as it wont reconize the boot for newer o/s.
we realy need system specs to help are the disk mbr or gpt a screen shot of drives in diskmanger will help

Thanks for replying. I was aware of the need for the older of the 2 OS's to be installed first. That shouldn't have been a problem in this case as win 7 was already installed on its own hard disk before I installed win 10.

Here is the image from disk manager. As you can see, all 3 drives are mbr. Sorry about getting which drive contained which OS wrong.



Hope that helps.

Right click start icon. Select Command Prompt (Admin). Run the following command in the command prompt window:

BCDBOOT D:\Windows /d /addlast
EXIT

Restart the computer.

Thank you. That worked a treat. One little thing though. Right clicking on the start icon only brought up a small menu of 4 items none of which were for the administrator command prompt. Fortunately a quick search on google provided a solution. Simultaneously pressing both the Windows key and 'X' brought up a menu that had Command Prompt (Admin) on it.

So thanks to you I now have a win 10/win 7 dual boot system.