Android Studio升级至3.1.2后同步项目遇连接超时求助

I recently upgraded Android Studio from version 3.x to 3.1.2. Before the upgrade, my project built and synced perfectly fine. But now every time I try to sync the project for building, I keep getting the error:

Connection timed out: connect

I've already tried creating a new project and switching to Gradle 4.7, but the problem still persists.

My Configuration Files: #

gradle-wrapper.properties

distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-all.zip

app module build.gradle

apply plugin: 'com.android.application'
android {
    compileSdkVersion 27
    defaultConfig {
        applicationId "st94.gmail.com.karaokegenerator"
        minSdkVersion 21
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        // multiDexEnabled true
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}
dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    testImplementation 'junit:junit:4.12'
    implementation 'com.android.support:appcompat-v7:27.1.0'
    implementation 'com.android.support:design:27.1.0'
    implementation 'com.mcxiaoke.volley:library:1.0.19'
    implementation "commons-io:commons-io:+"
    implementation 'com.github.castorflex.smoothprogressbar:library-circular:1.2.0'
    implementation 'com.google.code.gson:gson:2.6.2'
    implementation 'com.github.recruit-lifestyle:PlayPauseButton:1.0'
    implementation 'pub.devrel:easypermissions:1.2.0'
}

Project-level build.gradle

// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
    repositories {
        google()
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.2'
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}
allprojects {
    repositories {
        google()
        jcenter()
        maven { url "https://jitpack.io" }
    }
}
task clean(type: Delete) {
    delete rootProject.buildDir
}

Full Error Log: #

org.gradle.api.ProjectConfigurationException: A problem occurred configuring root project 'KaraokeGenerator'.
at org.gradle.configuration.project.LifecycleProjectEvaluator.addConfigurationFailure(LifecycleProjectEvaluator.java:94)
at org.gradle.configuration.project.LifecycleProjectEvaluator.doConfigure(LifecycleProjectEvaluator.java:66)
at org.gradle.configuration.project.LifecycleProjectEvaluator.access$100(LifecycleProjectEvaluator.java:34)
at org.gradle.configuration.project.LifecycleProjectEvaluator$ConfigureProject.run(LifecycleProjectEvaluator.java:110)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
at org.gradle.configuration.project.LifecycleProjectEvaluator.evaluate(LifecycleProjectEvaluator.java:50)
at org.gradle.api.internal.project.DefaultProject.evaluate(DefaultProject.java:666)
at org.gradle.api.internal.project.DefaultProject.evaluate(DefaultProject.java:135)
at org.gradle.execution.TaskPathProjectEvaluator.configure(TaskPathProjectEvaluator.java:35)
at org.gradle.execution.TaskPathProjectEvaluator.configureHierarchy(TaskPathProjectEvaluator.java:60)
at org.gradle.configuration.DefaultBuildConfigurer.configure(DefaultBuildConfigurer.java:38)
at org.gradle.initialization.DefaultGradleLauncher$ConfigureBuild.run(DefaultGradleLauncher.java:249)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
at org.gradle.initialization.DefaultGradleLauncher.configureBuild(DefaultGradleLauncher.java:167)
at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:126)
at org.gradle.initialization.DefaultGradleLauncher.getConfiguredBuild(DefaultGradleLauncher.java:104)
at org.gradle.internal.invocation.GradleBuildController$2.call(GradleBuildController.java:87)
at org.gradle.internal.invocation.GradleBuildController$2.call(GradleBuildController.java:84)
at org.gradle.internal

I'm stuck here and would really appreciate any feasible solutions to fix this sync issue.

内容的提问来源于stack exchange，提问作者ConductedClever