Bootcamp operating system missing error after resizing partition
Solution 1:
Firstly - Sorry for bringing up an old question - I just spent a year trying to find the answers and only found questions so I figured I'd answer a past one with my solution
Resize Bootcamp partition:
- Boot to MacOS and use disk utils to shrink OS X partition leaving unallocated space on hdd
<-- I believe you are at this point based on the empty space starting at 852326800 -->
Boot to GParted and use the copy/resize function to expand the windows partition to the left (this covers your extended space)
Boot back to OS X and use FDisk to mark the Bootcamp partition as bootable (Was partition 4 in my case and looks to be in your case)
-
Bless a Windows bootable USB before restart (with startup repair avaliable on it)
sudo bless -mount "/Volumes/**mountedusb**/" -legacy -setBoot -nextonly Boot to windows usb and run startup repair
Restart and you should be good.