Hi I am one of the experts here on Just Answer.com
Can you tell me the exact model of your linksys router?
It is an exisiting (not new) USB drive that was previously working and accessible (and remains so if I I connect it directly to a computer)
I have used the web interface to create a new share folder. I can see the partition/file hierarchy and create a share. But under "Total Space" web interface admin space it says "Not Exist" for both the old share (which used to work) and for the new share. And on my computer where I had saved a link into the USB drive it says "Location Not Available / access is denied". Other home computers on the network thar used to access the router drive have the same problem. (can delve one or two folder levels into the drive but then get access denied).
We did have power outage a few days ago and I am thinking perhaps some security setting (that I cannot find/figure out) was reset?
I did give r/w permissions to the share for both admin and guests.
I use the drive as a backup drive for photos and music files etc so wiping/reformatting it will be a bit of pain but maybe that is what I am done to. If I do that I gather I should reformat to an NTFS file structure.