Q: Having Difficulties Installing Windows 10 on Bootcamp

Hello!

So, I've been cracking my head open trying to install Windows 10 on Bootcamp. Why? Because every time I try to do so, I get this issue:

I've read in other threads that all I need to do is unmount the ISO through Disk Utility, which is what I've been doing.

However, every time I try to get Bootcamp ready to go, this little bugger gets mounted again by itself.

Does anyone know any fixes for this? The computer I'm trying to install it into is a MacBook Pro 13 Inch - Mid 2010. If it's not possible to install, would I just have to install Windows 7 and then upgrade it to Windows 10? The computer use to have Windows 10 installed, but I foolishly deleted it. It worked just fine.