diff --git a/src/main/java/cr0s/warpdrive/config/XmlPreprocessor.java b/src/main/java/cr0s/warpdrive/config/XmlPreprocessor.java
index 619f42d2..a51029af 100644
--- a/src/main/java/cr0s/warpdrive/config/XmlPreprocessor.java
+++ b/src/main/java/cr0s/warpdrive/config/XmlPreprocessor.java
@@ -1,5 +1,8 @@
 package cr0s.warpdrive.config;
 
+import java.util.Map.Entry;
+import java.util.TreeMap;
+
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;
@@ -18,9 +21,9 @@ public class XmlPreprocessor {
 	 * @return A string, which is empty if all the mods are loaded.
 	 * @throws InvalidXmlException
 	 */
-	public static String checkModRequirements(Element e) {
+	public static ModCheckResults checkModRequirements(Element e) {
 
-		String missingMods = "";
+		ModCheckResults modErrors = new ModCheckResults();
 
 		for (String mod : e.getAttribute("mods").split(",")) {
 
@@ -30,13 +33,17 @@ public class XmlPreprocessor {
 			if (mod.isEmpty())
 				continue;
 
-			if (!Loader.isModLoaded(mod)) {
-				missingMods = missingMods + mod + ", ";
-			}
+			if (mod.startsWith("!")) {
+
+				if (Loader.isModLoaded(mod.substring(1)))
+					modErrors.addMod(mod, "loaded");
+
+			} else if (!Loader.isModLoaded(mod))
+				modErrors.addMod(mod, "not loaded");
 
 		}
 
-		return missingMods;
+		return modErrors;
 	}
 
 	/**
@@ -54,11 +61,11 @@ public class XmlPreprocessor {
 
 			if (child instanceof Element) {
 
-				String res = checkModRequirements((Element) child);
+				ModCheckResults res = checkModRequirements((Element) child);
 
 				if (!res.isEmpty()) {
 					base.removeChild(child);
-					WarpDrive.logger.info("Removed child element " + child.getBaseURI() + " of element " + base.getBaseURI() + " because these mods arent loaded: " + res);
+					WarpDrive.logger.info("Removed child element " + child.getBaseURI() + " of element " + base.getBaseURI() + ", results: " + res);
 				} else {
 
 					doModReqSanitation(child);
@@ -70,4 +77,33 @@ public class XmlPreprocessor {
 
 	}
 
+	public static class ModCheckResults {
+
+		private TreeMap<String, String> mods;
+
+		public ModCheckResults() {
+			mods = new TreeMap<String, String>();
+		}
+
+		public void addMod(String name, String error) {
+			mods.put(name, error);
+		}
+
+		public boolean isEmpty() {
+			return mods.isEmpty();
+		}
+
+		@Override
+		public String toString() {
+			String s = "{";
+
+			for (Entry<String, String> e : mods.entrySet())
+				s = s + e.getKey() + ": " + e.getValue() + ", ";
+
+			return s + "}";
+
+		}
+
+	}
+
 }
diff --git a/src/main/java/cr0s/warpdrive/config/filler/FillerManager.java b/src/main/java/cr0s/warpdrive/config/filler/FillerManager.java
index e643d52e..ded653bc 100644
--- a/src/main/java/cr0s/warpdrive/config/filler/FillerManager.java
+++ b/src/main/java/cr0s/warpdrive/config/filler/FillerManager.java
@@ -15,8 +15,9 @@ import org.xml.sax.SAXException;
 import scala.actors.threadpool.Arrays;
 import cr0s.warpdrive.WarpDrive;
 import cr0s.warpdrive.config.InvalidXmlException;
-import cr0s.warpdrive.config.XmlPreprocessor;
 import cr0s.warpdrive.config.WarpDriveConfig;
+import cr0s.warpdrive.config.XmlPreprocessor;
+import cr0s.warpdrive.config.XmlPreprocessor.ModCheckResults;
 
 public class FillerManager {
 
@@ -69,10 +70,10 @@ public class FillerManager {
 
 		Document base = WarpDriveConfig.getXmlDocumentBuilder().parse(file);
 
-		String res = XmlPreprocessor.checkModRequirements(base.getDocumentElement());
+		ModCheckResults res = XmlPreprocessor.checkModRequirements(base.getDocumentElement());
 
 		if (!res.isEmpty()) {
-			WarpDrive.logger.info("Skippping filler data file " + file.getPath() + " because the mods " + res + " are not loaded");
+			WarpDrive.logger.info("Skippping filler data file " + file.getPath() + " because of: " + res);
 			return;
 		}
 
diff --git a/src/main/java/cr0s/warpdrive/config/structures/StructureManager.java b/src/main/java/cr0s/warpdrive/config/structures/StructureManager.java
index 672e73b8..ea9ca56d 100644
--- a/src/main/java/cr0s/warpdrive/config/structures/StructureManager.java
+++ b/src/main/java/cr0s/warpdrive/config/structures/StructureManager.java
@@ -13,8 +13,9 @@ import org.xml.sax.SAXException;
 
 import cr0s.warpdrive.WarpDrive;
 import cr0s.warpdrive.config.InvalidXmlException;
-import cr0s.warpdrive.config.XmlPreprocessor;
 import cr0s.warpdrive.config.WarpDriveConfig;
+import cr0s.warpdrive.config.XmlPreprocessor;
+import cr0s.warpdrive.config.XmlPreprocessor.ModCheckResults;
 
 
 public class StructureManager {
@@ -61,10 +62,10 @@ public class StructureManager {
 	private static void loadXmlStructureFile(File f) throws SAXException, IOException, InvalidXmlException {
 		Document base = WarpDriveConfig.getXmlDocumentBuilder().parse(f);
 
-		String res = XmlPreprocessor.checkModRequirements(base.getDocumentElement());
+		ModCheckResults res = XmlPreprocessor.checkModRequirements(base.getDocumentElement());
 
 		if (!res.isEmpty()) {
-			WarpDrive.logger.info("Skippping structure data file " + f.getPath() + " because the mods " + res + " are not loaded");
+			WarpDrive.logger.info("Skippping structure data file " + f.getPath() + " because of: " + res);
 			return;
 		}