T9 External HD will not download AutoCAD files or PDFs

[meb58]

I just purchased a t9 external HD and It will not accept most of the files in my documents.  This was an easy task for my Passport external HD...crazy.  

I attached a message that I received for every file being copied...I have no idea what this message means.  If I select yes, then all files download without any information in the folders...no drawings, no pdfs, no Word Docs either

[Addus]

My friend who works in the construction industry uses AutoCAD quite often. By the way, if you are a beginner and want to quickly understand AutoCAD, my friend recommends this tutorial at the link. Here are the main points and basic knowledge that are necessary to get started with AutoCAD.