Windows 7 dual boot problem

[Colin Webb]

I have had a dual boot system for several months which until now has worked fine.
For some reason Windows 7 which is on a separate drive to Windows 10 will not now boot, this has happened without any change to my computer.
I can boot into safe mode but can't figure what to do to rectify the problem.
Any suggestions?

 

[jefboyardee]

I have 7 and 10, on separate partitions, and there's been times when I get 10's splash screen but the loading twirly thing never appears. Usually I can just boot to 7, then restart and try 10 again. Other times, I have to boot to the 10 ISO or the MS System Repair DVD and tell them to fix 10's startup.

It usually doesn't report that it found anything to fix. But then, if I boot 7 and reboot to 10 again, it works. No idea why. Don't really care either, my real concern is keeping the 7 partition from 'upgrading' to 10.