package name is not determined in android studio

Question

i am using Android studio 1.5. and at when i click run i receive

unable to determine package name 

i checked the manifest file and it is as shown in the image below...but i do not know why the activities are marked with red even the app name and the icon as well.

please let me know how to fix this

build.gradle:

    apply plugin: 'com.android.application'

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.2"

    defaultConfig {
        applicationId "com.example.com.bt_11"
        minSdkVersion 21
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}


    dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:23.0.1'
    }

Answer 1

I followed the same steps as user2121 and eventually tried downgrading to Android Studio 1.4.1. Unlike user2121, I still got an error, however it was different than when on 1.5.1.

AndroidManifest.xml file not found

Upon searching for this new error, I found this StackOverflow answer which solved the problem for me on 1.5.1 as well as 1.4.1.