Error message for scheduled backups

I’ve connected and backed up data on my Mac laptop, but after assistance from WD and Apple, it does not perform scheduled backups. I get an error message: backup folder can not be created. Suggestions? Would uninstalling and reinstalling help? I may have I chosen encryption or some other special feature that’s causing this. I’d like to start over, keep it simple and hope it works. Thanks. 

Hi, what backup program are you using? Can you save files manually by using copy/paste or drag and drop? Also if you are using password protection, you always need to unlock the hard drive for the Mac to recognize it.