Trying to install Windows 10 via Bootcamp Assistant

The Mac used to have El Capitan but it was having issues and we wanted to go to High Sierra. Not wanting any issues, I installed OS X over an internet connection to wipe out the old OS and start fresh. I had set aside some space for the Windows OS but got the same error I have now. I thought I was getting the error because I had left some space for the Windows OS so I repeated the process except I didn't leave any extra space and figured I could create a partition with Boot Camp Assistant. When the reinstall finished I had 2 recovery HDs. I figured if I got a different error then before then the extra Recovery could be a problem but I'm still getting "The startup disk cannot be partitioned or restored to a single partition."

I am not sure how it happened but I'm told it shouldn't cause an issue. I tried to delete one but couldn't get it to go away. If its not causing a problem then I'm not that worried about it. I really need to nail down this Boot Camp issue.

Thank you for the reply.

I erased the drive but the 2nd Recovery HD was still there so I erased it to "exFAT" and then back to "Mac OS Extended (Journaled)" and the 2nd Recovery HD was gone. When I launched Boot Camp Assistant, all three boxes were available and I was able to continue without an error...so far. Thank you! I will let you know if anything else comes up

So I copied the ISO to the desktop and was able to get all the drivers installed on a USB but when it reboots to install Win 10 I get a gray screen. It when I came in this morning the screen was still gray. My understanding is that its supposed to reboot and look like a standard Win 10 install. From what I've read/watched I shouldn't need to put the ISO on a Flash drive

There are two that I have tried:

MD5 (SW_DVD5_Win_Pro_10_1703_64BIT_English_MLF_X21-36726.ISO) = bf519b145722a5534fcdb8e4224cae44

MD5 (Win10_x64.iso) = 986e2e17cf6b0b49141cd15699768e6e

The first is one that was provided to me and the second was one I downloaded from Microsoft last week at Download Windows 10 Disc Image (ISO File)

OK I will do that and let you know the result