@joecast 

I have not tried to do this, but using another vendor's router I was able to make it rescan.

On the USB drive is a .TPDLNA folder. If you take that drive to a PC and rename the folder (so you can restore it if this doesn't work) and then put it back on the router, the DLNA Server should rebuild it. Compared to my other router though the TP-Link (I have an A20 which is similar I hope) also had another folder, .dms that actually holder the database. That one too might need to be renamed.

Like I said, I've not tried this so I can be sure it would work. Rename both folder so they can be restored if it doesn't work. Doesn't work, delete the newly created files and restored the names to the saved old ones.

It might even be better to contact support, just in case they know a better way?

@IrvSp - Thanks!

This totally worked on my Archer AX6000.

I altered your suggestion slightly:

1. I turned off Media Sharing.
2. I mapped a network drive to the share.
3. I copied the .TPDLNA folder to my local drive.
4. I deleted it from the share.
5. I turned on Media Sharing.

The .TPDLNA folder should reappear and if you enter that folder you should see a database file called files.db and see the size grow as the router scans the drive.  Once the size stops growing, you are in business!

My database wasn't really corrupt; I was still serving up files, but I was getting some "ghost" folders when browsing from my DVD player.  Last night I downloaded some courses I bought and I downloaded straight to the drive instead of downloading to my computer and then copying to the share.  I noticed that when it downloaded it was going to a temp name and then getting renamed.  I think this confused the Media Sharing process.

In the .TPDLNA folder, in addition to the files.db there were two other hidden files called .fuse_hidden followed by a long hex number.  In reading up on "fuse" files, they are created when the system tries to delete a file but can't because another process has it in use.

So there was *DEFINITELY* some weirdness happening at some point.

Anyway, all better now.  Thanks again!

@toolsmythe 

The databases are nothing more than SQL databases.

I 'had' a TREMENDOUS fight with Netgear Support when many many years ago I had problems using the DLNA server. Same sort of stuff, maybe even worse? Ghost files and many duplicated and triplicated files. I could hardly playback anything. I couldn't get them to connect to my PC to show them (support somewhere in Asia and they claimed they didn't have capability). Sent I don't know how many screenshots. Nada, they still claimed it worked for them.

Finally figured out how to get thier attention. A collection of screenshot and DUMPS of the dataset.

This is a program that worked for me, https://sqlitebrowser.org/

You can look everywhere, and when there is a problem, it should be evident, here is what it looks like with my database:

Just root around in it... do need to understand the structure and pointers though.

@joecast 

I think that when the router is creating the server and the process fails it has to write/output the folder entry to the attached drive being used. It can't write to itself.  My reasoning is based on checking my LaCie external hard drive that I have had connected for a few years to the Archer C5. If it were normal for this folder is created on the connected drive, I would think that there would also be a .TPDLNA folder on that drive as well, right? The folder is not there. I was swapping out the LaCie with a 3.0 usb flash drive.

I could not move or delete, change attributes, etc on this .TPDLNA folder not even in DOS until I ran chkdsk. It fixed it.  Yes, I did rename it to _old. But then I remembered 0f chkdsk to fix corrupted files. 

You guys have fixed your issue by renaming the folder or moving it, but you still have it, right? For those who find this regarding the .TPDLNA folder, this worked for me.

1. Run CMD as administrator.
2. at the command prompt type:  chkdsk /f e:  (change e to the drive letter containing the .TPDLNA folder
3. run it by hitting enter.

The /f switch as usual is to: fix errors on disk

Then I was able to delete the folder and it's contents. I'm pretty sure there is a switch to delete the folder and all of it's content but  I think I had to drill down to the bottom folder and: del *.* the files first first and then the folder, and worked my way up and out.