Windows 10: BootMgr Is Missing After Update from Win7

I recently upgraded from Win 7 to Win10. The upgrade went smoothly with one big exception: after I boot Win 10 it inevitably crashes a day or two later with the dreaded "BootMgr is missing Press Ctrl-Alt-Del to restart" error message. To be clear, Win 10 starts and runs fine for a day or so and then crashes. Each time I have to restart Win10 with the start button on my computer, and lo and behold Win10 starts normally. I did not have this problem with Win7. I tried the usual recommended fixes: startup repair from the installation disk, and CHKDSK C: /f; but nothing has worked. At one point when I booted Win10 I was assigned a temporary profile, and I had to fix that through some registry entries. That problem apparently has disappeared, but the "BootMgr Is Missing" problem persists . Any ideas or suggestions would be much appreciated.

:)

 

Freeze just after bootscreen, after some updates or system changes

Thankyou for your reply,

The problem has been present for awhile and isn't a result of any one pinpointable recent update, so SR would most probably prove useless. As you'll notice, three standard tests have been applied and come back with no problems found.

Do you think that applying the boot fixes from the installation media would work ? As I've noted, even though I put a 4GB partition at the beginning of the drive, both OS's have their own "bootmgr" in their C:\ drives and the Win7 bootmgr seems to point
to the Win10 bootmgr - for the the first entry {bootmgr} it says F: for the Partition parameter (whereas the 10 says C

It wouldn't overly worry me if it was just Win10 that crapped out, but that updates to Win10 makes Win7 unbootable as well.

 

I have windows 10. Why is it trying to install itself?

I used this method and it killed my computer. Gave me the "BootMGR is missing Ctrl+Alt+Del to restart." and since i did not have a windows 10 thing, as i got a free upgrade from win7 i had to reinstall windows 7.