I found out (the hard way) that some newer Linux distros also break dual boot by doing something that prevents the user from booting into Windows, whatever the flavor is. What I did to get around this was to 1). Program Windows first, remove the hardware, program Linux unto another drive, reinserting Windows ensuring it was the primary boot to O/S, then use BCDedit to dual boot the disks, or 2). Install Windows, install an older version of Linux (20.X), use BEDedit to fix the dual boot capabilities, then upgrade Linux to the current version. A lot of work, yes, but it works.
In the General/Chat forum, on a thread titled Microsoft Fixes Windows Update That Broke GRUB in Dual-Boot Systems, ducttape45 wrote: I found out (the hard way) that some newer Linux distros also break dual boot by doing something that prevents the user from booting into Windows, whatever the flavor is. What I did to get around this was to 1). Program Windows first, remove the hardware, program Linux unto another drive, reinserting Windows ensuring it was the primary boot to O/S, then use BCDedit to dual boot the disks, or 2). Install Windows, install an older version of Linux (20.X), use BEDedit to fix the dual boot capabilities, then upgrade Linux to the current version. A lot of work, yes, but it works.
I installed Linux 'along side' a fresh install of Windows and couldn't even see windows from that point forward.
I believe it had to do with the format of the flash drive(s) used to install each. Windows install flash was probably, by default MBR. The Linux flash was GBT, I think. So after installing Linux alongside I was surprised I couldn't see windows. When creating install flash for windows, the format is silently negotiated. I tried swapping BIOS from Legacy and then I could see Windows boot, but not Linux. Or it's all just a strange coincidence! I'm guessing this is the problem because, sadly, I had done a version of that before!
I may try your fix, or just set it aside someplace safe so later, you can save me hours of troubleshooting. :D