If you own Command & Conquer: Generals – Zero Hour , EA released an official update (Patch 1.04) that removes the SafeDisc requirement. Note: This patch is for Zero Hour , but it often resolves the base game's issues if you own The First Decade collection.
The long-running community fix doesn't involve buying a new game, but rather a quick trip into the Windows Registry Editor to change the values manually: Locating the Key : Most users navigate to command and conquer generals serial key already in use