I tried to format my Toshiba external hard drive for Asus pc use and MacBook air use. The HD worked on pc so I moved files off of hard drive onto pc then tried to format for Mac. Now I can open mac files but my Asus shows the hard drive but will not open anything. I think I messed up when I used time machine. I am not computer savvy. So most importantly, I really would like my photos on the Asus moved back to the hard drive. And if possible move the mac photos to the hard drive, nothing else matters.How can I do this? Should I wipe the hard drive clean and start over?