Success, I think.
I created a folder in my external drive "(My Name"), then created a folder inside called VGHD, and THEN I cut and pasted both "Models" and "Data" into the VGHD folder from my C drive location.
I guess because I have 742 cards, it's taking 4 hours and 45 minutes to copy the Models folder with 344 GB worth of 25,172 items.
After I have the Data and Models files copied onto my external hard drive, can I delete them from the C drive? If so, how do I proceed so when I open VGHD, it goes to the external drive, and subsequent files are downloaded into the external drive?
I sure hope I haven't made a mistake and will lose everything or not be able to access my cards.
THANK YOU so much for your help!