You have a code from eBay, but the installer says "Invalid Serial Number" or "Code already in use." Here is your troubleshooting guide:
Unlike a full sequel, City Life Edition 2008 was primarily a repackaged version of the original game, often bundled with its expansion, City Life: World Edition (which added new maps, buildings, and an enhanced editor). The “2008” edition was distributed in certain regions (including parts of Europe and Asia) as a budget or “Gold” release, typically optimized for Windows Vista and XP. It included the latest patches and sometimes minor texture updates. City Life Edition 2008 Serial Code
However, unlike modern digital storefronts, physical copies of City Life Edition 2008 required a Serial Code – a unique alphanumeric string (e.g., XXXX-XXXX-XXXX-XXXX) printed on the manual or a sticker inside the DVD case. This code was used to authenticate the installation and, in some cases, to access online features or modding tools. You have a code from eBay, but the
City Life 2008 is not available on mainstream stores like Steam, GOG, or Origin. However, a bundle titled City Life: The Complete Collection was briefly sold on GamersGate in 2010. If you purchased it then, the serial code is in your email or account library. Because SecuROM tracks unique installs, reusing a code
Avoid G2A, Kinguin, or similar grey-market key resellers. City Life 2008 is so obscure that keys sold there are often:
Because SecuROM tracks unique installs, reusing a code across multiple PCs can trigger this. Solution: Download a No-CD crack (available from GameBurnWorld or MegaGames) and replace the original CityLife.exe. This bypasses the serial check entirely.