diff --git a/core/AppEng.java b/core/AppEng.java
index f4c41b6a..c05bed1a 100644
--- a/core/AppEng.java
+++ b/core/AppEng.java
@@ -22,11 +22,13 @@ import appeng.integration.IntegrationType;
 import appeng.server.AECommand;
 import appeng.services.Profiler;
 import appeng.services.VersionChecker;
+import appeng.transformer.MissingCoreMod;
 import appeng.util.Platform;
 
 import com.google.common.base.Stopwatch;
 
 import cpw.mods.fml.common.FMLCommonHandler;
+import cpw.mods.fml.common.Loader;
 import cpw.mods.fml.common.Mod;
 import cpw.mods.fml.common.Mod.EventHandler;
 import cpw.mods.fml.common.event.FMLInitializationEvent;
@@ -64,7 +66,8 @@ public class AppEng
 	// "after:gregtech_addon;after:Mekanism;after:IC2;after:ThermalExpansion;after:BuildCraft|Core;" +
 
 	// depend on version of forge used for build.
-	"required-after:appliedenergistics2-core;" + "required-after:Forge@[" // require forge.
+	// "required-after:appliedenergistics2-core;" +
+	"required-after:Forge@[" // require forge.
 			+ net.minecraftforge.common.ForgeVersion.majorVersion + "." // majorVersion
 			+ net.minecraftforge.common.ForgeVersion.minorVersion + "." // minorVersion
 			+ net.minecraftforge.common.ForgeVersion.revisionVersion + "." // revisionVersion
@@ -106,6 +109,9 @@ public class AppEng
 	@EventHandler
 	void PreInit(FMLPreInitializationEvent event)
 	{
+		if ( !Loader.isModLoaded( "after:appliedenergistics2-core" ) )
+			throw new MissingCoreMod();
+
 		Stopwatch star = Stopwatch.createStarted();
 		configPath = event.getModConfigurationDirectory().getPath() + File.separator + "AppliedEnergistics2" + File.separator;
 
diff --git a/transformer/MissingCoreMod.java b/transformer/MissingCoreMod.java
new file mode 100644
index 00000000..9ee4d19e
--- /dev/null
+++ b/transformer/MissingCoreMod.java
@@ -0,0 +1,63 @@
+package appeng.transformer;
+
+import net.minecraft.client.gui.FontRenderer;
+import net.minecraft.client.gui.GuiErrorScreen;
+import cpw.mods.fml.client.CustomModLoadingErrorDisplayException;
+
+public class MissingCoreMod extends CustomModLoadingErrorDisplayException
+{
+
+	private static final long serialVersionUID = -966774766922821652L;
+	private boolean deobf = false;
+
+	@Override
+	public void initGui(GuiErrorScreen errorScreen, FontRenderer fontRenderer)
+	{
+		Class clz = errorScreen.getClass();
+		try
+		{
+			clz.getField( "mc" );
+			deobf = true;
+		}
+		catch (Throwable e)
+		{
+
+		}
+	}
+
+	@Override
+	public void drawScreen(GuiErrorScreen errorScreen, FontRenderer fontRenderer, int mouseRelX, int mouseRelY, float tickTime)
+	{
+		int offset = 10;
+		drawCenteredString( fontRenderer, "Sorry, couldn't load AE2 Properly.", errorScreen.width / 2, offset += 15, 0xffffff );
+		drawCenteredString( fontRenderer, "Please make sure that AE2 is installed into your mods folder.", errorScreen.width / 2, offset += 15, 0xeeeeee );
+
+		offset += 15;
+
+		if ( deobf )
+		{
+			offset += 15;
+			drawCenteredString( fontRenderer, "In a developer environment add the following too your args,", errorScreen.width / 2, offset += 15, 0xffffff );
+			drawCenteredString( fontRenderer, "-Dfml.coreMods.load=appeng.transformer.AppEngCore", errorScreen.width / 2, offset += 15, 0xeeeeee );
+		}
+		else
+		{
+			drawCenteredString( fontRenderer, "You're launcher may refer to this by diffrent names,", errorScreen.width / 2, offset += 15, 0xffffff );
+
+			offset += 5;
+
+			drawCenteredString( fontRenderer, "MultiMC calls this tab \"Loader Mods\"", errorScreen.width / 2, offset += 15, 0xeeeeee );
+			drawCenteredString( fontRenderer, "Magic Launcher calls this tab \"External Mods\"", errorScreen.width / 2, offset += 15, 0xeeeeee );
+			drawCenteredString( fontRenderer, "Most other launchers refer to this tab as just \"Mods\"", errorScreen.width / 2, offset += 15, 0xeeeeee );
+
+			offset += 15;
+
+			drawCenteredString( fontRenderer, "Also make sure that the AE2 file is a .jar, and not a .zip", errorScreen.width / 2, offset += 15, 0xffffff );
+		}
+	}
+
+	public void drawCenteredString(FontRenderer fontRenderer, String string, int x, int y, int colour)
+	{
+		fontRenderer.drawStringWithShadow( string, x - fontRenderer.getStringWidth( string.replaceAll( "\\P{InBasic_Latin}", "" ) ) / 2, y, colour );
+	}
+}
\ No newline at end of file