usb - Windows 8.1 installation: Which drive is the F drive?

I am doing a clean install of Windows 8.1 on an old PC. It was purchased as download from Microsoft Store and written to and booted from a USB flash drive.

It went through all of these steps:

1. Copying Windows Files


2. Getting files ready for installation


3. Installing features


4. Installing updates

Then at "Getting finished" I am stuck at this stupid dialog box.

Please unplug the following external drive and click OK to restart your computer and finish installing Windows.

F:

How do I tell what physical drive this is? Can I drop to command prompt during installation? And is it safe to unplug it while powered on?

There is no external hard drive connected, none that I can see. There is no USB or FireWire drive connected externally. I think it sees one of the internal drives as external... in some weird way?!

Answer

1. Press Shift+F10 to bring up a command prompt.


2. 
   

   Type the following command:

   
   

   wmic logicaldisk get caption,filesystem,size,volumename
   

Example output

Caption  FileSystem  Size          VolumeName       
C:       NTFS        366997504     System Reserved  
D:       NTFS        20974428160   System           
E:       FAT32       80004153344   80 GB            
F:       FAT32       7721713664    ESD-USB          
G:       NTFS        53884649472   Datadisk N
H:       NTFS        315183595520  Backup           
I:       NTFS        59073925120   Datadisk         
J:       NTFS        130668294144                   
K:                                                  
L:                                                  
X:       NTFS        533640192     Boot             

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