If the online button is grayed out or the game crashes when connecting, you might have a "broken install" from a past update. MKX LAG FIX FOR MULTIPLAYER GUIDE - Steam Community 25 May 2015 —
Mortal Kombat X Online Fix typically refers to a Steamworks Fix Mortal Kombat X Online Fix
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To develop a blog post about the " Mortal Kombat X Online Fix If the online button is grayed out or