I have an external hard drive plugged into my router via USB.  In the router setup interface, I can see the hard drive (i.e., the drive name and the amount of space), but it doesn't list any folders to share, despite the existence of several folders on the hard drive. Consequently, I can't access the drive through windows explorer.

Troubleshooting so far...

I've turned off the access authentication.

I've tried using another flash drive in the router - it works.

I've tried sharing the drive in question through a laptop connected to the internet - it works.

Other info...

I've previously had this exact configuration and have been able to access the drive.

It stopped working after I unplugged the hard drive from my router and plugged it into my NVIDIA Shield; however, the flash drive mentioned above was also plugged into the NVIDIA shield and it works.