Unable to resolve all dependencies in android studio 3.0

[vipin.saini]

I am getting these errors while syncing gradle:-

Error:Unable to resolve dependency for ':app@debug/compileClasspath': Could not resolve com.android.support:appcompat-v7:26.1.0.

Error:Unable to resolve dependency for ':app@debug/compileClasspath': Could not resolve com.android.support:design:26.1.0.

Error:Unable to resolve dependency for ':app@debugAndroidTest/compileClasspath': Could not resolve com.android.support.test:runner:1.0.1.

Error:Unable to resolve dependency for ':app@releaseUnitTest/compileClasspath': Could not resolve junit:junit:4.12.

Error:Unable to resolve dependency for ':app@debugAndroidTest/compileClasspath': Could not resolve com.android.support.test.espresso:espresso-core:3.0.1.


METHODS TRIED
i have tried adding GOOGLE MAVEN REPO, mavencentral all with url & without url.
i have tried deleting .gradle folder from C:\Users\<username>/.gradle.
i have tried gradle offline work and online work, both end up with same error message.
tried clean project & rebuilding.
tried INVALIDATE CACHE & RESTART.
tried degrading the android studio version.

I AM USING WINDOWS 64BIT WITH 4GB OF RAM AND DUAL CORE 2.0 GHZ PROCESSOR, AND ANDROID VERSION 3.0, GRADLE VERSION 4.1 & 4.3(LATEST), I HAVE INSATLLED ALL THE NECESSARY TOOLS & EVERYTHING UPDATED IN SDK MANAGER. ANDROID SUPPORT REPOSITORY & GOOGLE OFFLINE REPOSITORY BOTH INSTALLED.

WHENEVER I TRY TO SYNC IT WITH OFFLINE WORK IT END UP WITH ERROR (NO CACHED VERSION OF THIS (DEPENDENCY IS FOUND), AND WHENEVER I TRY TO SYNC WITH ONLINE WORK, THE ERRORS ARE SAME LISTED ABOVE IN BOTH CASES.
I HAVE TRIED EVERYTHING FROM STACK OVER FLOW & YOUTUBE.

BUILD.GRADLE PROJECT:MY APPLICATION.
// 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:3.0.0'


// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}

allprojects {
repositories {
google()
jcenter()
}
}

task clean(type: Delete) {
delete rootProject.buildDir
}


BUILD.GRADLE MODULE:APP
apply plugin: 'com.android.application'

android {
compileSdkVersion 26
buildToolsVersion "26.0.2"
defaultConfig {
applicationId "com.example.vipinsaini.myapplication"
minSdkVersion 15
targetSdkVersion 26
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}

dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'com.android.support:appcompat-v7:26.1.0'
implementation 'com.android.support.constraint:constraint-layout:1.0.2'
implementation 'com.android.support:design:26.1.0'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.1'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'
}


CAN ANYONE PLZ HELP ME SOLVE THIS ISSUE. I am new to android studio plz omit mistakes.

 

[Klimaszewski]

Add google() to allprojects node in your root build.gradle file
allprojects {
repositories {
jcenter()
google()
}
}

 

[mar7]

Hey,

I have a same problem. I tried to do your solution, but already exist this code in build.gradle file.
I will be happy to another solution.

Thanks.

 

[funloft]

Try to Invalidate Cache/Restart that got the problem fixed for me

 

[Robbie02081979]

Unable to Resolve Dependencies

After much research and headache... Go to File\Settings\Gradle. Deselect the "Offline work" box. Now you can connect and download any necessary or missing dependencies.

 

[Ayo2android]

Worked, thank you.

 

[suryasuriya]

i tried invalidate and restart then delete .gradle file then uncheck the offline work but no use not clear the appcompact error