diff --git a/app/src/main/java/net/kdt/pojavlaunch/MainActivity.java b/app/src/main/java/net/kdt/pojavlaunch/MainActivity.java
index cd207f496..a7f3dbdb6 100644
--- a/app/src/main/java/net/kdt/pojavlaunch/MainActivity.java
+++ b/app/src/main/java/net/kdt/pojavlaunch/MainActivity.java
@@ -986,51 +986,20 @@ public class MainActivity extends AppCompatActivity implements OnTouchListener,
 	public void fixRSAPadding() throws Exception {
 		// welcome to the territory of YOLO; I'll be your tour guide for today.
 
-		System.out.println("Before: " + KeyFactory.getInstance("RSA") + " ; " + KeyFactory.getInstance("RSA").getProvider().toString());
-
 		try {
-			/*
-			 System.out.println(Cipher.getInstance("RSA"));
-			 System.out.println(Cipher.getInstance("RSA/ECB/PKCS1Padding"));
-			 */
-
-			Cipher rsaPkcs1Cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
-			Cipher rsaCipher = Cipher.getInstance("RSA");
-/*
-			for (Provider.Service ser : rsaPkcs1Cipher.getProvider().getServices()) {
-				System.out.println(" - " + ser.getType() + ", " + ser.getAlgorithm());
-			}
-*/
-			Provider.Service servicePkcs1 = rsaPkcs1Cipher.getProvider().getService("Cipher", "RSA/ECB/PKCS1Padding");
-			Provider rsaProvider = rsaCipher.getProvider();
-
-			Map pkcs1Map = new ArrayMap();
-			for (Map.Entry entry : servicePkcs1.getProvider().entrySet()) {
-				pkcs1Map.put(entry.getKey(), entry.getValue());
-			}
-
-			if (Build.VERSION.SDK_INT < 24) {
-				rsaProvider.putAll(pkcs1Map);
+			if (android.os.Build.VERSION.SDK_INT > 23) { // Nougat
+				// GetInstance.getServices("KeyPairGenerator", algorithm);
+				// Since Android 7, it use sun.security.jca.GetInstance
+				
+				Class.forName("sun.security.jca.GetInstance")
+					.getDeclaredMethod("getServices", String.class, String.class)
+					.invoke(null, new Object[]{"Cipher", "RSA"});
 			} else {
-				// Method rsaMethod_clear = rsaProvider.getClass().getDeclaredMethod("implClear");
-				Method rsaMethod_putAll = rsaProvider.getClass().getDeclaredMethod("implPutAll", Map.class);
-				// rsaMethod_clear.setAccessible(true);
-				rsaMethod_putAll.setAccessible(true);
-
-				// rsaMethod_clear.invoke(rsaProvider);
-				rsaMethod_putAll.invoke(rsaProvider, pkcs1Map);
+				ArrayList<Provider.Service> rsaList = Services.getServices("Cipher.RSA");
+				ArrayList<Provider.Service> rsaPkcs1List = Services.getServices("Cipher.RSA/ECB/PKCS1PADDING");
+				rsaList.clear();
+				rsaList.addAll(rsaPkcs1List);
 			}
-
-			/*
-			 if (android.os.Build.VERSION.SDK_INT >= 23) { // Marshmallow
-			 // FUUUUU I DON'T KNOW FIXME
-			 } else {
-			 ArrayList<Provider.Service> rsaList = Services.getServices("Cipher.RSA");
-			 ArrayList<Provider.Service> rsaPkcs1List = Services.getServices("Cipher.RSA/ECB/PKCS1PADDING");
-			 rsaList.clear();
-			 rsaList.addAll(rsaPkcs1List);
-			 }
-			 */
 		} catch (Throwable th) {
 			th.printStackTrace();
 			
@@ -1058,10 +1027,7 @@ public class MainActivity extends AppCompatActivity implements OnTouchListener,
 					}
 				});
 		}
-
-
-		System.out.println("After: " + KeyFactory.getInstance("RSA") + " ; " + KeyFactory.getInstance("RSA").getProvider().toString());
-
+		
 		/*
 		 Provider provider = KeyFactory.getInstance("RSA").getProvider();
 		 System.out.println("Before: " + provider.getService("KeyService", "RSA"));
diff --git a/app/src/main/java/net/kdt/pojavlaunch/Modifiable.java b/app/src/main/java/net/kdt/pojavlaunch/Modifiable.java
new file mode 100644
index 000000000..9031b8e88
--- /dev/null
+++ b/app/src/main/java/net/kdt/pojavlaunch/Modifiable.java
@@ -0,0 +1,35 @@
+package net.kdt.pojavlaunch;
+
+import java.util.*;
+import java.lang.reflect.*;
+
+// This class simply get the modifiable original Collection from unmodifable one.
+public class Modifiable
+{
+	public static <E> Collection<E> modifyCollection(Collection<? extends E> collection) {
+        if (collection == null) {
+            throw new NullPointerException("collection == null");
+        } else if (collection.getClass().getSimpleName().startsWith("Unmodifiable")) {
+			Field collectionField = null;
+			try {
+				collectionField = Class.forName("java.util.Collections$UnmodifiableCollection").getDeclaredField("c");
+			} catch (Throwable th) {
+				th.printStackTrace();
+			}
+			
+			if (collectionField != null) {
+				collectionField.setAccessible(true);
+				try {
+					return (Collection<E>) collectionField.get(collection);
+				} catch (Throwable th) {
+					th.printStackTrace();
+				}
+			}
+		}
+        return (Collection<E>) collection;
+    }
+	
+	public static <E> Set<E> modifySet(Set<? extends E> set) {
+		return (Set<E>) modifyCollection(set);
+    }
+}