diff --git a/app/src/main/assets/java_sandbox.policy b/app/src/main/assets/java_sandbox.policy
index 33a4e02dc..755dbe2c0 100644
--- a/app/src/main/assets/java_sandbox.policy
+++ b/app/src/main/assets/java_sandbox.policy
@@ -5,8 +5,11 @@
 grant {
     permission java.io.FilePermission "${java.io.tmpdir}/*", "read, write, delete";
     permission java.io.FilePermission "${pojav.path.minecraft}/*", "read, write, delete";
+
+    permission java.util.PropertyPermission "java.net.preferIPv4Stack", "write";
 };
 
 deny {
+    permission java.io.FilePermission "${pojav.path.private.account}/*", "read, write, delete"
     permission java.io.FilePermission "<<ALL FILES>>", "write, delete, execute"
-}
\ No newline at end of file
+}
diff --git a/app/src/main/java/net/kdt/pojavlaunch/Tools.java b/app/src/main/java/net/kdt/pojavlaunch/Tools.java
index 5a934b85e..b9123853b 100644
--- a/app/src/main/java/net/kdt/pojavlaunch/Tools.java
+++ b/app/src/main/java/net/kdt/pojavlaunch/Tools.java
@@ -78,9 +78,12 @@ public final class Tools
     public static void getJavaArgs(Context ctx, List<String> javaArgList) {
         List<String> overrideableArgList = new ArrayList<String>();
 
+        overrideableArgList.add("-Djava.security.manager");
+        overrideableArgList.add("-Djava.security.policy=java_sandbox.policy");
+        
         overrideableArgList.add("-Djava.home=" + Tools.DIR_HOME_JRE);
         overrideableArgList.add("-Djava.io.tmpdir=" + ctx.getCacheDir().getAbsolutePath());
-        // overrideableArgList.add("-Djava.library.path=" + JREUtils.LD_LIBRARY_PATH);
+        
         overrideableArgList.add("-Duser.home=" + new File(Tools.DIR_GAME_NEW).getParent());
         overrideableArgList.add("-Duser.language=" + System.getProperty("user.language"));
         // overrideableArgList.add("-Duser.timezone=GMT");
@@ -88,6 +91,9 @@ public final class Tools
         overrideableArgList.add("-Dos.name=Linux");
         overrideableArgList.add("-Dos.version=Android-" + Build.VERSION.RELEASE);
 
+        overrideableArgList.add("-Dpojav.path.minecraft=" + Tools.DIR_GAME_NEW);
+        overrideableArgList.add("-Dpojav.path.private.account=" + Tools.DIR_ACCOUNT_NEW);
+        
         // javaArgList.add("-Dorg.lwjgl.libname=liblwjgl3.so");
         // javaArgList.add("-Dorg.lwjgl.system.jemalloc.libname=libjemalloc.so");