diff --git a/app/src/main/cpp/MicroPhoto.cpp b/app/src/main/cpp/MicroPhoto.cpp
index 652222ff..7077c5cd 100644
--- a/app/src/main/cpp/MicroPhoto.cpp
+++ b/app/src/main/cpp/MicroPhoto.cpp
@@ -299,11 +299,11 @@ Java_com_xypower_mpapp_MicroPhotoService_init(
     env->SetObjectField(pThis, fieldId, modelName);
 
     bool udpOrTcp = (networkProtocol != 0); // 0: tcp
-    const char *appPathStr = env->GetStringUTFChars(appPath, 0);
-    const char *ipStr = env->GetStringUTFChars(ip, 0);
-    const char *cmdidStr = env->GetStringUTFChars(cmdid, 0);
-    const char *simcardStr = env->GetStringUTFChars(simcard, 0);
-    const char *tfCardPathStr = env->GetStringUTFChars(tfCardPath, 0);
+    const char *appPathStr = appPath == NULL ? NULL : env->GetStringUTFChars(appPath, 0);
+    const char *ipStr = ip == NULL ? NULL : env->GetStringUTFChars(ip, 0);
+    const char *cmdidStr = cmdid == NULL ? NULL : env->GetStringUTFChars(cmdid, 0);
+    const char *simcardStr = simcard == NULL ? NULL : env->GetStringUTFChars(simcard, 0);
+    const char *tfCardPathStr = tfCardPath == NULL ? NULL : env->GetStringUTFChars(tfCardPath, 0);
 
     JavaVM* vm = NULL;
     jint ret = env->GetJavaVM(&vm);
@@ -314,25 +314,25 @@ Java_com_xypower_mpapp_MicroPhotoService_init(
 
     CTerminal* pTerminal = NewTerminal(protocol);
 
-    CPhoneDevice* device = new CPhoneDevice(vm, pThis, appPathStr, NETID_UNSET, versionCode);
+    CPhoneDevice* device = new CPhoneDevice(vm, pThis, MakeString(appPathStr), NETID_UNSET, versionCode);
     device->SetListener(pTerminal);
     device->UpdateSignalLevel(signalLevel);
     device->SetBuildTime(buildTime / 1000);
-    device->UpdateSimcard(simcardStr);
-    device->UpdateTfCardPath(tfCardPathStr == NULL ? "" : std::string(tfCardPathStr));
+    device->UpdateSimcard(MakeString(simcardStr));
+    device->UpdateTfCardPath(MakeString(tfCardPathStr));
 
-    pTerminal->InitServerInfo(appPathStr, cmdidStr, ipStr, port, udpOrTcp, encryptData);
+    pTerminal->InitServerInfo(MakeString(appPathStr), MakeString(cmdidStr), MakeString(ipStr), port, udpOrTcp, encryptData);
     // pTerminal->SetPacketSize(1 * 1024);	// 1K
 #ifdef USING_NRSEC
     pTerminal->InitEncryptionInfo(simcardStr, "/dev/spidev0.0", "");
 #endif
     bool res = pTerminal->Startup(device);
 
-    env->ReleaseStringUTFChars(appPath, appPathStr);
-    env->ReleaseStringUTFChars(ip, ipStr);
-    env->ReleaseStringUTFChars(cmdid, cmdidStr);
-    env->ReleaseStringUTFChars(simcard, simcardStr);
-    env->ReleaseStringUTFChars(tfCardPath, tfCardPathStr);
+    if (appPathStr != NULL) env->ReleaseStringUTFChars(appPath, appPathStr);
+    if (ipStr != NULL) env->ReleaseStringUTFChars(ip, ipStr);
+    if (cmdidStr != NULL) env->ReleaseStringUTFChars(cmdid, cmdidStr);
+    if (simcardStr != NULL) env->ReleaseStringUTFChars(simcard, simcardStr);
+    if (tfCardPathStr != NULL) env->ReleaseStringUTFChars(tfCardPath, tfCardPathStr);
 
     if (!res)
     {