Abandon the installation of win7. According to my personal experience, from yesterday afternoon 1 to 3: 30 in the morning, I downloaded three original iso versions of win7, all of which failed to install at 3.34G/3. 19G/3.42G for the same reason as you. Win7 can be installed normally in July, and it was installed only yesterday. I can't sign it. If I disable signing, I will restart the blue screen. It's really nb. After reinstalling n times, the error is still the same. There is no choice but to modify win 10. It turned out to be a success once. After personal judgment, it should be that 15 inch boot camp assistant does not support the installation of win7 after the os system is updated. .

The attachment is newly installed win 10, please check it. Win8 hasn't tried, you can try.