Having issues with a brand new WD Elements 5TB drive. I swap it between computers occasionally, always ejecting beforehand. However if I eject from my PC, use the drive elsewhere and then plug it back into my PC it is not recognied. The only way to get it to show up is to load up Disk Management every time, or restart.
As a recommendation, test the drive using the WD DLG Tool to see if is giving you any specific errors.
Also make sure to always connect the drive to the back USB ports of the computer and the power cable to the wall outlet, this will guarantee that the unit is getting enough power to load up properly.