Windows doesn't boot unless I use windows boot manager

[CB Hilarious]

Windows doesn't boot unless I uses windows boot manager. I have no idea what's causing it.

 

[LukeFatwalker]

Likely there's some damage done to your Master Boot Record (MBR) this can be solved relatively well by simply resetting the MBR.

If the issue persists, I'd recommend backing your data up with a disk imager (i.e. Macrium Reflect, Drive Cloner Rx, etc) and re-install the OS.

Finally, once back in Windows make sure to run a backup, you can use a disk imager or snapshot tool (i.e. Comodo Time Machine, RollBack Rx) whichever you have a preference for.

 

[BFG-9000]

Do you need to select a line in the boot manager because the default one doesn't work?

If so, you can change the default one to the line that works at System-->Advanced System Settings-->Startup and Recovery Settings-->Default Operating System