accessing hidden partitions in windows 10

Did you even know that there were hidden partitions? I didn't until I tried to access one!

I needed at add a file to a hidden EFI (boot) partition on a bootable USB drive. Unfortunately, Windows Explorer does not "mount" these partitions by default and there doesn't seem to be any easy way of doing this from the normal Windows interface. However, this method works well 😄

Open an Administrator Command Prompt window by pressing start, typing "Command", right clicking on "Command Prompt" and choosing "Run as Administrator".

In the Command Prompt window, type mountvol, disregard help message in the beginning and notice the list of GUID-based paths of all volumes known to Windows, e.g.:

What a long list of unmounted partitions.

As you can see, there are a lot of partitions with the statement "*** NO MOUNT POINTS ***" underneath. These are hidden from Windows Explorer. It's impossible to tell which partition is the one you are looking for from this list, so we have to inspect them one at a time.

Select the first string "\\?\Volume{XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}\" and press CTRL+C to copy the string.

At the prompt, type "start " and then right click your mouse next to the space. The copied string should appear.

Press Enter and you should immediately see an Explorer Window.

If this is not the partition you need, close Explorer down and repeat the operation.

Eventually, I get this partition...