You have created a folder called "USB Drive" beneath your "Public Documents" folder which exists whether or not any external USB drive is connected. Whatever is in that folder is in that folder and has no connection to whatever may or may not be on any of your USB drives.
Actual USB drives, when attached, will appear in the File Explorer/Windows Explorer tree with a drive letter assigned to them and will disappear from said tree when removed.
And if you are looking in the Network part of the tree there must be a level between "Network" and "Users" which is typically the name of the machine on which that Users folder resides.
Edited by britechguy, 09 April 2018 - 02:37 PM.
Brian AKA Bri the Tech Guy (website in my user profile) - Windows 10 Home, 64-Bit, Version 1809, Build 17763
Presenting the willfully ignorant with facts is the very definition of casting pearls before swine.
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