Gradle Sync Failed Error in Android Studio: How to Fix

What Does the "Gradle Sync Failed" Error Mean

The Gradle Sync Failed error occurs when Android Studio cannot complete the process of synchronizing the project with Gradle. In the logs, you will see a message like: Gradle sync failed: Could not resolve all files for configuration... or Failed to resolve: com.android.tools.build:gradle. This error blocks the project build because Gradle fails to download necessary dependencies from repositories (such as Maven Central, Google Maven). Synchronization starts automatically when you open a project, modify a build.gradle file, or manually via the Sync Now button.

Common Causes

The Gradle Sync Failed error is usually caused by one of the following specific issues:

1. Missing or unstable internet connection — Gradle cannot download dependencies from remote repositories.
2. Incorrect proxy settings — if you are behind a corporate proxy, Android Studio or your system may be using incorrect parameters.
3. Version conflicts — incompatibility between Gradle, Android Gradle Plugin (AGP), or installed library versions.
4. Corrupted local Gradle cache — the cache in the ~/.gradle/caches folder contains broken or incomplete files.
5. Blocking by antivirus or firewall — security software may prohibit access to Gradle repositories (e.g., repo.maven.apache.org).
6. Outdated or incorrect repository URLs — the build.gradle files specify inaccessible or changed addresses.

Solutions

Solution 1: Check Internet Connection and Proxy Settings

Ensure your computer has internet access and can reach Gradle repositories.

1. Open your browser and go to https://gradle.org — if the page does not load, there is a network issue.
2. If you use a proxy, check the settings:
   • In Android Studio: File → Settings → Appearance & Behavior → System Settings → HTTP Proxy.
   • Select Auto-detect proxy settings or manually enter the proxy address and port.
   • Click Check connection and enter https://repo.maven.apache.org — it should return 200 OK.
3. If a proxy is not required, set it to No proxy.
4. Restart Android Studio and try to sync the project (click the Sync Now button in the toolbar).

Solution 2: Clear Gradle Cache and Restart

A corrupted Gradle cache is a frequent cause of this error. Invalidating the cache resolves the problem in most cases.

1. In Android Studio, go to File → Invalidate Caches and Restart....
2. In the dialog, select Invalidate and Restart.
3. After the restart, Android Studio will automatically start synchronization. If it doesn't, click Sync Now.
4. If the error persists, delete the cache manually:
   • Close Android Studio.
   • Delete the Gradle cache folder:
     • Windows: C:\Users\<Your_Name>\.gradle\caches
     • macOS/Linux: ~/.gradle/caches
   • Restart Android Studio and wait for dependencies to re-download (this may take several minutes).

Solution 3: Disable Offline Mode

Offline work mode forces Gradle to use only local files, which causes an error if dependencies are missing.

1. Open Gradle settings: File → Settings → Build, Execution, Deployment → Gradle (on macOS: Android Studio → Preferences → Build, Execution, Deployment → Gradle).
2. In the Gradle settings section, find the Offline work option.
3. Uncheck the box if it is selected.
4. Click Apply and OK.
5. Run the synchronization again.

Solution 4: Update Gradle and Android Gradle Plugin

Version incompatibility causes failures. Ensure you are using the latest stable versions.

1. Open the project-level build.gradle file (not the module-level one).
2. Find the dependencies block and update the AGP classpath:

   dependencies {
       classpath 'com.android.tools.build:gradle:8.2.0' // use the latest stable version
   }
   

3. Open the gradle/wrapper/gradle-wrapper.properties file and update the Gradle distribution:

   distributionUrl=https\://services.gradle.org/distributions/gradle-8.4-all.zip
   

   Check the official Android Developer website for current versions.
4. After making changes, click Sync Now.
5. If Android Studio suggests a migration, follow the prompts.

Solution 5: Configure Antivirus and Firewall Exceptions

Antivirus software can block Gradle's access to repositories.

1. Temporarily disable your antivirus and firewall (e.g., Windows Defender, Avast, Kaspersky).
2. Try to sync the project — if the error disappears, blocking is the issue.
3. Add exceptions:
   • For the Gradle folder: C:\Users\<Your_Name>\.gradle (Windows) or ~/.gradle (macOS/Linux).
   • For processes: java.exe, javaw.exe (Android Studio uses Java).
   • For URLs: https://repo.maven.apache.org, https://dl.google.com.
4. Restart your antivirus and Android Studio.

Solution 6: Reinstall Android Studio (Last Resort)

If all previous solutions fail, your Android Studio installation may be corrupted.

1. Back up important projects and settings (the .idea and gradle folders in your project directory).
2. Uninstall Android Studio:
   • Windows: via Control Panel → Programs and Features.
   • macOS: drag the app to the Trash and delete the folders ~/Library/Application Support/Google/AndroidStudio* and ~/.android.
   • Linux: delete the installation folder and ~/.AndroidStudio*.
3. Download the latest version from the official website and install it.
4. On first launch, specify SDK paths and configure proxy settings if needed.
5. Open your project and wait for synchronization to complete.

Prevention

To avoid a recurring Gradle Sync Failed error, follow these recommendations:

• Maintain a stable internet connection — use a wired connection or reliable Wi-Fi. Avoid restricted public networks.
• Keep tools updated regularly — install Android Studio, Gradle, and AGP updates via Help → Check for Updates.
• Configure proxy settings correctly — if working on a corporate network, confirm proxy parameters with your IT department and add exceptions for Gradle repositories.
• Do not disable offline mode unnecessarily — enable it only for builds without internet, then return to online mode.
• Add antivirus exceptions — at minimum for the ~/.gradle folder and Java processes.
• Use fixed versions — in build.gradle, specify exact library versions instead of using + (e.g., implementation 'com.squareup.retrofit2:retrofit:2.9.0' instead of 2.9.+) to avoid unexpected updates.