I'm looking in the right place for the files as I did copier all the files created on PC but has not copied files created on MAC. its strange because same problem when I copied to the MAC H.D

I open both drives and copy & past , the same way I been doing for the past 15 years  on PC setups with no problems.

I'm thinking the Portable H.D might need re-formatting to suit MAC ! but then can you not save files created on a PC ? but that does not explain as way can't backup all Files to the MAC H.D we were told by the computer tech' that AutoCAD is compatible between both computers    MAC & PC but is it for saving files ?  

Need to get the computer tech' to have a look and see if he can explain it.

Thanks for your help anyway I will get to the bottom of this

We are having so much problems that we are going back to PC