If you have obtained a version of the game that requires the Photon Launcher, the setup generally involves the following steps:

Photon Launcher does not always update automatically. You may need to download the latest game files from your original source whenever Kinetic Games releases a patch.

Open the main folder where you installed the game and find a file named Launcher.exe or Phasmophobia-MP.exe .

Ensure you have updated DirectX and Microsoft Visual C++ Redistributables installed, as the launcher depends on these libraries.