: Launch the game directly via the executable. Ensure your antivirus does not mistakenly flag the steam_api.dll (the emulator file) as a threat.
: Open the extracted folder and look for the main game application, usually portal.exe or portal2.exe .
: To play with others, ensure everyone is on the same network and using the same version of the Goldberg-patched files. Important Notes
: Always scan downloaded files from third-party "portal" sites for malware, as these are unofficial distributions.