Where do Kerbal Space Program add-ons have to be placed (with the Steam version)?

Question

I use the Steam version of Kerbal Space Program and I don't know where add-ons have to be installed.

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Answer 1

Once you've downloaded an addon, you have to put the files (unzip them if they come in a .zip archive file) in the GameData folder, for example on Windows 64 bits this is this path:

C:\Program Files (x86)\Steam\SteamApps\common\Kerbal Space Program\GameData

If you use another OS see the official Wiki to find the root directory of Kerbal Space Program.

Example: I installed the WaypointManager add-on in the GameData directory and the result is a C:\Program Files (x86)\Steam\SteamApps\common\Kerbal Space Program\GameData\WaypointManager dictory containing the add-on files: WaypointManager.cfg, WaypointManager.dll, etc.

Source: Tutorial:Installing Addons (official wiki).