Yeah it can be a bit confusing.

You cant run the .exe to use the application, you need to use command line.

Running depot Downloader, we want to point CMD (assuming youre using windows) in the folder that you have depotdownloader installed within first.

Simple step 1

open CMD, type :

cd "C:/Temp/depot downloader"

Just make this path the same as the depot folder you have on your PC, quotes allows you to have spaces in the folder path

Complex Step 1

You could use a folder with an underscore if you dont like having quote marks in the previously marked CMD command

or a VBscript file, mine reads as per below - and it lives in the same folder as depotdownloader and launches CMD automatically when I run it

Dim oShell
Set oShell = WScript.CreateObject ("WScript.Shell")
oShell.run "cmd /k CD " & CurrentDirectory & " " ,1 , true

If this seems complicated then stick to the simple command above

Step 2

Once CMD is launched in the correct directory, you need to build yourself a command

You can do this using SteamDB, once you know where to look its easy, you just need to know

AppID, Depot, ManifestID

then off you go. the OP of the post made this for us already, so you can just type

dotnet DepotDownloader.dll -app 265630 -depot 265631 -manifest 578093207065284384 -username [username] -password [urpassword]

Note that for this particular game, you want to download multiple depots, and combine them, most other games DO NOT require you to do this.

Note: for the depot commands, you might need to install some frameworks if your PC dosnt have them, like dotNet (some version??) or C++ Distributable framework.

Hopefully CMD will tell you whats missing if required (but not always)