: Check Windows Security > Virus & Threat Protection for any quarantined files from your GRAW installation directory. Restoring these often allows the installer to recognize your product key as the Multiplayer ID.
Modern users often encounter a specific "bug" during installation where the game refuses to accept the key or the installer hangs. This is frequently caused by Windows Defender or other antivirus software: : The installer uses a legacy file called KeyChecker.exe ghost recon advanced warfighter multiplayer id key new