I am editing photos using CC 2015 and I when I try to save a file I will get a disk not available error. I get this error regardless of whether I am trying to save to my computer's hard drive or a external hard drive. When I shut down photoshop and reboot, It works for a few images and then I get the message again. Understand, it is not a disk full error but not available error. Not sure if there is a difference.