As an addendum to the thread below, easyre for windows 7 worked for me. I had this exact same problem at work. https://www.wilderssecurity.com/threads/how-to-convert-gpt-uefi-to-mbr-windows-bootable.339321/page-2 I don't work for the company that makes easyre. I wanted to let everyone to know as it saved me a lot of time.