I'm trying to run an flutter app but for some reason that I can't figure out, it won't run. This is what I'm getting when I run. I did add the flutter/bin bath to the system path, but that didn't work either. This happened after I reformatted my windows. What I did exactly was: 

* install Android Studio
* download flutter sdk
* added flutter plugin in the Android Studio.

and this is what i did the first time before I formatted my PC. And it worked.

```
Launching lib\main.dart on Mi 9T in debug mode...
Running Gradle task 'assembleDebug'...

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:signingConfigWriterDebug'.
> java.io.IOException: Unable to delete file: E:\codes\flutter\im_poor\build\app\intermediates\signing_config\debug\out\signing-config.json

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 5s
Finished with error: Gradle task assembleDebug failed with exit code 1

```

and this what flutter doctor said: 

```
C:\flutter_windows_v1.9.1+hotfix.6-stable\flutter\bin\flutter.bat doctor --verbose
[√] Flutter (Channel stable, v1.12.13+hotfix.8, on Microsoft Windows [Version 10.0.17763.1098], locale en-US)
    • Flutter version 1.12.13+hotfix.8 at C:\flutter_windows_v1.9.1+hotfix.6-stable\flutter
    • Framework revision 0b8abb4724 (5 weeks ago), 2020-02-11 11:44:36 -0800
    • Engine revision e1e6ced81d
    • Dart version 2.7.0

[!] Android toolchain - develop for Android devices (Android SDK version 29.0.3)
    • Android SDK at C:\Users\Joseph\AppData\Local\Android\sdk
    • Android NDK location not configured (optional; useful for native profiling support)
    • Platform android-29, build-tools 29.0.3
    • Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
    • Java version OpenJDK Runtime Environment (build 1.8.0_212-release-1586-b04)
    X Android license status unknown.
      Try re-installing or updating your Android SDK Manager.
      See https://developer.android.com/studio/#downloads or visit https://flutter.dev/setup/#android-setup for detailed instructions.

[√] Android Studio (version 3.6)
    • Android Studio at C:\Program Files\Android\Android Studio
    • Flutter plugin version 44.0.2
    • Dart plugin version 192.7761
    • Java version OpenJDK Runtime Environment (build 1.8.0_212-release-1586-b04)

[√] Connected device (2 available)
    • Mi 9T               • d8f2ce60      • android-arm64 • Android 10 (API 29)
    • AOSP on IA Emulator • emulator-5556 • android-x86   • Android 9 (API 28) (emulator)

! Doctor found issues in 1 category.
Process finished with exit code 0

```