opening Win32DiskImager it detects the SD but then looks for an existing image name to open in order to write it to this SD,the Win32DiskImager + BalenaEtcher method, I've done that more than 2 dozen times
just plug the source disk (disregard if windoze doesnt read the linux partion, it doesnt, wont matter!)
let Win32DiskImager "read" the source so it can save it to a file in a windows folder that you direct it to (just dont forget to put the .img after the file name, ex: RPi2BJessie07172019.img)
after that, its time to use Etcher to flash the saved image to the target microSD card (this time I'll assume that you already know how to use Etcher)
I cannot open the SD to read it and write to file (CMIIW)!
Same about BalenaEtcher !