Bootcamp Windows 10 not recognizing external hard drive unless "Create and format hard disk partitions" is used.

I am having trouble with my external hard drive not being recognized on bootcamp windows 10 unless I add the drive letter and path. When I do add the drive letter, it always has an error and says it needs to be scanned. When I click scan and repair, no window pops up. It used to work without control panel until I updated the bootcamp drivers. The system restarted and ever since then I have to go through control panel to get the hard drive recognized. I have reinstalled bootcamp but that doesn't work. I don't want to format the hard drive because I want to keep the files on it. I tried to run first aid on mac os as well and I still have the same poroblem. Every time I startup using bootcamp, I need to use control panel to get the hard drive recognized. Any help would be greatly appreciated.