basically, you need to restart your mac in recovery mode, go to menu utilities and open terminal, type crsutil status to check if it is enabled or disabled, then you can use csrutil disable or csrutil enable. Obs.: if your MacOS complain, you need to disable the CSR before change this. That's it, now when you open the Bootcamp assistant you can use the option that allows you to create a USB install boot disk. it will ask if you want to replace it, then you answer yes. Save this file, go back to the contents of the Boot Camp Assistant and drag the newly edited file into. In my case I changed from Macbook7,2 to MacBookPro8,2. If it is like PreUSBBootSupportedModels, change the name to USBBootSupportedModels, expand this line and at the item0, edit and write down your MacBook model as a string value. Open this ist file with a plist file editor or xcode, then look for a line saying 'USBBootSupportedModels'. Then find the file ist and drag and drop to a whatever folder you created before.

go to your application>utilities, select the Boot Camp Assistant app, right click > show packages content.

So, for those who can't create the USB install disk, here some tip.

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