Mapping to an external harddrive

I am starting a new string on the item because my description was wrong.

I have an external hardrive on my system connected to a USB port. I can
access the drive on my network but cannot access any folders on the drive
even though I have the drive marked as shared and I also have the folders
marked as shared.

I can access the harddrives that in packaged in my system with no problems.
Only the external HD gives me problems.

Any suggestions on what I might be doing wrong

Bruce A. Julseth