Since Windows 8 my PrimFilm 1800u slide and film scanner will not work. Apparently the PrimFilm driver is not certified by Microsoft and neither PrimFilm nor Microsoft care. I did finally find a workaround fortunately.
I followed the instructions on the youtube video named "How to install unsigned drivers on Windows 10 - By TotallydubbedHD". (https://www.youtube.com/watch?v=StkR3D2d5WI) I used the old driver "SF_Eng_1.3".
I followed my handwritten instructions below which are real rough -
Windows key + I
Get charms bar.
left click on power
shift - reset
Get Troublelshoot screen
Go to device Manager
Get red message not digitally assigned
After this Windows 10 worked fine with the scanner. It has been a long time.