Minecraft wiki entry for Creating_Forge_mods, associated text: After refreshing gradle, open the gradle panel and double-click the "genIntellijRuns" entry in the "fg_runs" folder. This will create new run configurations that allow your mod to be run. Next, open the "Edit configurations" window of Run settings and look approximately halfway down, for "Use classpath of module." Click on its dropdown field, and select the option that ends with .main, then click Apply. If the settings you just finished editing were for the Minecraft Client, click on Minecraft Server and repeat the steps to set the classpath. [TODO: Is this necessary anymore? It was already set]