"Unofficial Game Modification" Notification + Black Screen Fix
If you've dabbled with core mods or recently approved of a new Windows update, it's likely you'll run into this notification while launching the game.
The good news? The notification is innocuous and easily fixable following the steps below.
Just press "Continue".
Yup, that easy! Pressing "Continue" will make the game launch normally. If you're unable to see this notification from a black screen, hold ALT + TAB at the same time to find it.
2. Fix your core mods.
Core mods such as NRAAS ErrorTrap and simler90's Gameplay Core Mod are known to cause this pop-up. The mods' platform version can be mismatched to your platform's version, prompting this notification.
ErrorTrap offers a download for different platforms: EA App, 64bit Mac version, Steam version and Retail Disk version.
Gameplay Core Mod version on MTS causes this pop-up when used on Steam, EA App and Mac versions of the game. You can download a fix here (SimFileShare link).










