diff --git a/HMCL/build.gradle b/HMCL/build.gradle
index 7afabd5d7..c969403af 100644
--- a/HMCL/build.gradle
+++ b/HMCL/build.gradle
@@ -25,7 +25,7 @@ if (!hasProperty('mainClass')) {
     ext.mainClass = 'org.jackhuang.hellominecraft.launcher.Main'
 }
 
-def buildnumber = System.getenv("BUILD_NUMBER") == null ? ".4" : "."+System.getenv("BUILD_NUMBER")
+def buildnumber = System.getenv("BUILD_NUMBER") == null ? ".5" : "."+System.getenv("BUILD_NUMBER")
 
 String mavenGroupId = 'HMCL'
 String mavenVersion = '2.3.5' + buildnumber
diff --git a/HMCL/src/main/java/org/jackhuang/hellominecraft/launcher/Launcher.java b/HMCL/src/main/java/org/jackhuang/hellominecraft/launcher/Launcher.java
index 36045a124..36f8848c4 100644
--- a/HMCL/src/main/java/org/jackhuang/hellominecraft/launcher/Launcher.java
+++ b/HMCL/src/main/java/org/jackhuang/hellominecraft/launcher/Launcher.java
@@ -24,7 +24,6 @@ import java.net.URLClassLoader;
 import java.util.ArrayList;
 import javax.swing.SwingUtilities;
 import org.jackhuang.hellominecraft.C;
-import org.jackhuang.hellominecraft.HMCLog;
 import org.jackhuang.hellominecraft.utils.functions.TrueFunction;
 import org.jackhuang.hellominecraft.utils.StrUtils;
 import org.jackhuang.hellominecraft.views.LogWindow;
@@ -98,8 +97,10 @@ public final class Launcher {
         }
 
         Method minecraftMain;
+        URLClassLoader ucl = new URLClassLoader(urls, URLClassLoader.getSystemClassLoader().getParent());
+        Thread.currentThread().setContextClassLoader(ucl);
         try {
-            minecraftMain = new URLClassLoader(urls, URLClassLoader.getSystemClassLoader()).loadClass(mainClass).getMethod("main", String[].class);
+            minecraftMain = ucl.loadClass(mainClass).getMethod("main", String[].class);
         } catch (ClassNotFoundException | NoSuchMethodException | SecurityException t) {
             MessageBox.Show(C.i18n("crash.main_class_not_found"));
             println("Minecraft main class not found.");
@@ -113,15 +114,14 @@ public final class Launcher {
         try {
             minecraftMain.invoke(null, new Object[]{(String[]) cmdList.toArray(new String[cmdList.size()])});
         } catch (Throwable throwable) {
-            HMCLog.err("Cought exception!");
             String trace = StrUtils.getStackTrace(throwable);
             final String advice = MinecraftCrashAdvicer.getAdvice(trace);
             MessageBox.Show(C.i18n("crash.minecraft") + ": " + advice);
 
-            LogWindow.instance.warning(C.i18n("crash.minecraft"));
-            LogWindow.instance.warning(advice);
-            LogWindow.instance.warning(trace);
             LogWindow.instance.setExit(TrueFunction.instance);
+            System.err.println(C.i18n("crash.minecraft"));
+            System.err.println(advice);
+            System.err.println(trace);
             LogWindow.instance.setVisible(true);
             
             flag = 1;
diff --git a/HMCL/src/main/java/org/jackhuang/hellominecraft/launcher/Main.java b/HMCL/src/main/java/org/jackhuang/hellominecraft/launcher/Main.java
index e77eb6a1c..9ab032da3 100644
--- a/HMCL/src/main/java/org/jackhuang/hellominecraft/launcher/Main.java
+++ b/HMCL/src/main/java/org/jackhuang/hellominecraft/launcher/Main.java
@@ -102,7 +102,7 @@ public final class Main implements Runnable {
     }
 
     public static String launcherName = "Hello Minecraft! Launcher";
-    public static byte firstVer = 2, secondVer = 3, thirdVer = 5, forthVer = 4;
+    public static byte firstVer = 2, secondVer = 3, thirdVer = 5, forthVer = 5;
     public static int minimumLauncherVersion = 16;
 
     /**