I recently installed Windows 10 via a partition from Boot Camp Assistant but had a lot of issues with it; mainly the fact that after about 10 minutes of using it Windows crashed and took me to a blue screen that told me I would have to run a disk repair to fix Windows. When running Windows repair, it would get stuck in an endless loop of re-booting over and over again and it took me about 30 minutes of that to be able to boot using Opt to select my Macintosh HD as the startup disk.
I decided I didn't need to use Windows badly enough to deal with that at the moment so I figured I'd delete my Windows partition. Boot Camp Assistant wouldn't let me delete the partition through there because it told me the partition wasn't journaled and Disk Utility wouldn't allow me to delete the partition either. This is when I read some help saying to boot my Mac using internet recovery (Cmd+Opt+R) and run Disk Utility from there to delete the partition.
This worked and I no longer show any Windows info Disk Utility but today when I restarted my Mac it booted me up to the Windows blue screen showing that I need to run disk repair again just like it did before I removed the partition. Does anybody know how/why this is still coming up (especially as my startup disk)? I would really love to get everything Windows off of my computer without having to do a fresh install of El Capitan (ver. 10.11.5) since I just did one a few weeks back.