Skate probably means to say that you put the wrong folder location into this field, circled in red here.
What you should put there is probably C:\Users[your name]\Saved Games\DCS
or C:\Users[your name]\Saved Games\DCS.openbeta
in my case, it is D:\Doc\Saved Games\DCS.openbeta but that is because I moved the Saved Games folder to a different drive.
EDIT: some explanation
DCS has an install or program files folder, typically in C:\Program Files\Eagle Dynamics\DCS and a Saved Games folder, which is the one I mentioned above.
In the install folder, all files are kept that are the same for everybody: maps, simulation, default skins and missions, and the modules themselves. Everything that you get when you download DCS, or a module.
In the Saved Games folder, DCS puts everything that is different for every player: graphics and sound settings, keybinds, snapviews, custom user-made missions, custom skins.
As a bonus, most mods that add a new aircraft/boat/vehicle to the game (such as the awesome, free, fully clickable, A-4 Skyhawk) can also be put in Saved Games.
The advantage of this is that the DCS Updater can update the entire install folder without a risk of deleting any of the custom skins/missions/keybinds you made.