This is something that has happened to me before and I assume that a folder in Windows had become corrupted. But I just replicated the problem and it's connected with how VLC interacts with Windows. So this isn't trouble shooting... it's more of a Windows only bug.
I save VLC snapshots in a folder called Captured Frames. A few months ago I noticed that this was no longer a folder I could open... but it would grow in size if I took more video snapshots. Well, it happened again... and this time I know why. I'd moved the replacement Captured Frames folder to another drive. Forgetting this I took some more video frames and I again ended up with the same corrupted "folder".
When I delete something in Windows... then delete the folder it was in... but try to restore the item... Windows will create a new folder. But when VLC isn't finding the folder designated for snapshots, VLC creates a replacement container that's not a real folder. It's a container that Windows can't access. When I click on it, I get a list of apps to choose from to open it. Yet Windows considers it a folder and I can't have the VLC container AND a real folder with the same names.
So I want to report this as a bug... but also ask if anyone has ideas on whether the contents of these containers can ever be salvaged.
Thanks!
Using Win 8.1 and VLC 2.2.1