diff --git a/app/src/main/java/com/xypower/mpapp/MainActivity.java b/app/src/main/java/com/xypower/mpapp/MainActivity.java
index dafd10e8..a9f14973 100644
--- a/app/src/main/java/com/xypower/mpapp/MainActivity.java
+++ b/app/src/main/java/com/xypower/mpapp/MainActivity.java
@@ -267,7 +267,7 @@ public class MainActivity extends AppCompatActivity {
 
                 AppConfig curAppConfig = retrieveAndSaveAppConfig();
 
-                if (TextUtils.isEmpty(appConfig.cmdid) || TextUtils.isEmpty(appConfig.server) || appConfig.port == 0) {
+                if (TextUtils.isEmpty(curAppConfig.cmdid) || TextUtils.isEmpty(curAppConfig.server) || curAppConfig.port == 0) {
                     return;
                 }
                 Intent intent = new Intent(MainActivity.this, MicroPhotoService.class);
@@ -576,15 +576,19 @@ public class MainActivity extends AppCompatActivity {
                 dataPath.mkdirs();
             }
 
-            inputStreamReader = new InputStreamReader(new FileInputStream(new File(appPath + "App.json")), "UTF-8");
-            bufferedReader = new BufferedReader(inputStreamReader);
-            String line;
             StringBuilder stringBuilder = new StringBuilder();
-            while ((line = bufferedReader.readLine()) != null) {
-                stringBuilder.append(line);
+            File file = new File(dataPath, "App.json");
+            if (file.exists()) {
+                inputStreamReader = new InputStreamReader(new FileInputStream(file), "UTF-8");
+                bufferedReader = new BufferedReader(inputStreamReader);
+                String line;
+
+                while ((line = bufferedReader.readLine()) != null) {
+                    stringBuilder.append(line);
+                }
             }
 
-            JSONObject jsonObject = new JSONObject(stringBuilder.toString());
+            JSONObject jsonObject =stringBuilder.length() > 0 ? (new JSONObject(stringBuilder.toString())) : (new JSONObject());
 
             jsonObject.put("CMDID", cmdid);
             jsonObject.put("Server", server);