Eventually I had to leave a call-back number. Sadly, I waited on hold a long time then got disconnected! I had to call back yet again and work my way up to the 2nd tier and waited on hold again. I worked my way up to 2nd tier support level in order to talk to a more tech-savvy person. No help there. I finally was told that El Capitan is not supported by my WD drive, therefore this is an issue for Apple and not their problem.
I tried everything, incl running their utilities, downloading new firmware and calling WD support. I have a WD My Passport For Mac external hard drive that worked fine, then I upgraded my OSX to El Capitan.
