Still gave the same 'Non-System Disk' error.

So I removed the BootCamp Partition and tried with another SanDisk 32 GB USB. On EFI Systems, Windows Can Only Be Installed to GPT.' Tried to install by using the bootcamp partition that was already created, but couldn't since Windows wouldn't let me - 'The Selected Disk Has an MBR Partition Table. Tried rebooting with the option key, EFI Boot was displayed. I then proceeded to partition the drive using BootCamp's Install Windows 7 or later option, then BootCamp automatically restarted the macbook and should have displayed the install windows screen (like it did when I installed Windows 8 Previously a year ago), but instead booted to a black screen that displayed 'Non-System Disk Press Any Key to Reboot'. I then proceeded to download the Windows 10 圆4 iso file and then used it to create a bootable usb along with support software installed in it. (Installed Windows 8 using the sameīootCamp then displays - Create a Windows 7 or later install disk, Download the latest support software from Apple, and Install Windows 7 or later version. BootCamp did not allow my model to create a bootable USB, so I tweaked ist and added my model identifier in the USBSupportedModels list to make a bootable USB. Now I am trying to Install any version of Windows on my Macbook Air again.

I have previously Installed Windows 8 on my macbook air and removed it. MacBook Air 11-Inch, Late 2010 Processor - 1.6 GhZ Intel Core 2 Duo Memory - 4 GB 1067 MHz DDR3 Graphics - NVIDIA GeForce 320M 256 MB OS - macOS El Capitan, Version 10.11.6

Windows 7 on macbook air