I have a problem with booting Windows 10. I use Windows 10 and Ubuntu 14.04 and first I instantly got back to GRUB when selecting Windows 10 then I booted from Windows 10 installer media and ran following commands:
bootrec.exe/fixmbr bootrec.exe/fixboot bootrec.exe/scanos bootrec.exe/rebuildbcd
I reinstalled GRUB and now I don't get back into GRUB after selecting Windows 10 but I get a blackscreen showing _ and Windows does still not boot.
After I executed bootrec.exe/scanos I got the following message:
The searching after Windows-installations was successful. Number of identified installations: 1  C:\Windows.old\Windows (sorry for bad translation)
Notice: I have updatet from Windows 7 to Windows 10
For me it looks like Windows does not consider the current OS but I can't think of anything that could help.