This is what you need to do.
Right click the desktop and select "New" and then "Text Document"
Rename the shortcut "Drive-x.exe" The x can be your choice. C is the obvious, and then subsequent shortcuts must be different. (D E etc)
Drag it to the taskbar and pin it.
Delete the desktop shortcut.
Right click the taskbar icon, and right click the drive-x entry. Select "Properties"
The target will appear as, for example, Users\Administrator\Desktop\drive-c.exe
Delete all in the Target, and "run" field, to just the basic drive (C:\)
Ready to go!