I'm running Windows 2003. I am an admin on this particular machine. I tried to delete a folder, but something went slightly wrong. When I navigate to its parent I can see it in there. 

When I double click the folder, I get the error message: `D:\Path\to\folder is not accessible. Access is denied.`

When I try to delete the folder, I get `Cannot delete foldername: Access is denied. Make sure the disk is not full or write-protected and that the file is not currently in use.` and I get the same when I try to rename it or create a similarly-names folder.

There is ample room left on that drive, so the disk isn't full at all.

Is there anything else I haven't thought of? I don't really want to restart the machine, but I will if I have to.