Ошибка Android при создании подписанного APK: keystore.jks не найден для подписи config 'externalOverride'

Я получаю эту ошибку, когда пытаюсь создать подписанный APK. Недавно я обновился до API 23, но сгенерировал APK: s после этого. Я смущен. Обратиться за помощью и сообщить, как решить эту проблему. Здесь ошибка

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:validateExternalOverrideSigning'.
> Keystore file /Users/me/Desktop/final apps/keystore.jks not 
found for signing config 'externalOverride'.

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

И журнал

Information:Gradle tasks [:app:assembleRelease]
:app:preBuild UP-TO-DATE
:app:preReleaseBuild UP-TO-DATE
:app:checkReleaseManifest
:app:preDebugBuild UP-TO-DATE
:app:prepareComAndroidSupportAppcompatV72311Library UP-TO-DATE
:app:prepareComAndroidSupportSupportV42311Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesAppindexing810Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesBasement810Library UP-TO-DATE
:app:prepareReleaseDependencies
:app:compileReleaseAidl UP-TO-DATE
:app:compileReleaseRenderscript UP-TO-DATE
:app:generateReleaseBuildConfig UP-TO-DATE
:app:generateReleaseAssets UP-TO-DATE
:app:mergeReleaseAssets UP-TO-DATE
:app:generateReleaseResValues UP-TO-DATE
:app:generateReleaseResources UP-TO-DATE
:app:mergeReleaseResources UP-TO-DATE
:app:processReleaseManifest UP-TO-DATE
:app:processReleaseResources UP-TO-DATE
:app:generateReleaseSources UP-TO-DATE
:app:compileReleaseJavaWithJavac
Note: Some input files use or override a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
:app:compileReleaseNdk UP-TO-DATE
:app:compileReleaseSources
:app:lintVitalRelease
:app:transformClassesWithDexForRelease
:app:mergeReleaseJniLibFolders
:app:transformNative_libsWithMergeJniLibsForRelease
:app:processReleaseJavaRes UP-TO-DATE
:app:transformResourcesWithMergeJavaResForRelease
:app:validateExternalOverrideSigning FAILED
Error:Execution failed for task ':app:validateExternalOverrideSigning'.
> Keystore file /Users/me/Desktop/final apps/keystore.jks not found for
signing config 'externalOverride'. 

Вот мой Gradle

apply plugin: 'com.android.application'

android {
compileSdkVersion 23
buildToolsVersion "23.0.2"


defaultConfig {
    applicationId "com.waffles.vatsandbats"
    minSdkVersion 14
    targetSdkVersion 23
}

buildTypes {
    release {
        minifyEnabled false
         proguardFiles getDefaultProguardFile('proguard-android.txt'),
'proguard-rules.txt'     
    }
}
}

dependencies {

compile files('libs/acra-4.7.0-javadoc.jar')
compile files('libs/acra-4.7.0-sources.jar')
compile files('libs/acra-4.7.0.jar')
compile 'com.google.android.gms:play-services-appindexing:8.1.0'
compile files('libs/activation.jar')
compile files('libs/mail.jar')
compile files('libs/additionnal.jar')
compile 'com.android.support:support-v4:23.1.1'
compile 'com.android.support:appcompat-v7:23.1.1'


}