Can' boot to any OS

[Jeremin]

So today I tried to install Windows 10 as a second OS with a USB. After the installation was complete the setup made a reboot to my laptop and after the Samsung logo it loads to Windows 10 setup again where it began. Windows 10 is installed to C: partition. If I change boot order from USB to HDD first then after Samsung logo I get BOOTMGR is missing. Please help as I don't want to lose my files from C: (I was dumb and didn't made a backup)

 

[rgd1101]

Did you create a new partition for windows 10?

 

[Jeremin]

Yes I did. I installed Win 10 to 50GB partition which I created. Right now when I'm trying to boot the after Samsung logo I only get: "Bootmgr is missing Press Ctrl+Alt+Del to restart"

 

[rgd1101]

If you have recovery disk you could do a recovery on your previous os.
Else take the HDD out, connect to another computer, backup your data, reinstall the os.

 

[Jeremin]

My friend borrowed me an USB with Hiren's BootCD. I copied all my files to external HDD through "Mini Windows XP" and formatted everything. Now everything is fine after the installation of new Win 7 except I can't boot straight from my HDD. I get NTLDR is missing Press CTRL + ALT + DEL. I can only get to Windows 7 if I boot to Hiren's BootCD through USB and go to Dos Programs --- Next --- Grub4Dos --- Boot From Hard Drive. Is it possible to boot straight from HDD not through USB all the time. I think that it's some problem about partitions that were made earlier. I have already deleted the 50GB made earlier.