How to Fix "Could Not Resolve All Files for Configuration ':app:debugRuntimeClasspath'"

If you've seen this error in Android Studio or a Gradle-based project, you're not alone. It's one of the more common — and frustrating — build errors developers encounter, especially after updating dependencies, switching branches, or setting up a project on a new machine. Here's what it actually means and what drives it.

What This Error Is Telling You

The error message refers to Gradle's dependency resolution process. When you build an Android app, Gradle attempts to gather every library, module, and file your project needs at runtime. The debugRuntimeClasspath configuration specifically covers the files needed to run your app in debug mode.

When Gradle says it "could not resolve all files," it means one or more of those required files couldn't be located, downloaded, or matched to a compatible version. The build stops because it can't proceed without a complete classpath.

This is not a code error — it's a build system error. Your Java or Kotlin logic may be perfectly fine. The problem lives in dependency declarations, network access, version conflicts, or local environment configuration.

Common Causes of This Error

Understanding why this happens is the first step to diagnosing it in your own project.

🔗 Missing or Unresolvable Dependencies

The most frequent trigger is a dependency declared in your build.gradle file that Gradle can't find. This happens when:

• The repository hosting the library isn't listed in your settings.gradle or top-level build.gradle (e.g., missing mavenCentral(), google(), or a custom repo URL)
• The version number you specified doesn't exist or has been yanked
• A transitive dependency (a dependency of a dependency) has a conflict or is no longer available

Version Conflicts Between Libraries

When two libraries depend on different versions of the same module, Gradle has to resolve the conflict. Sometimes it can't — particularly if a library requires a version that conflicts with another constraint in your dependency tree. This is sometimes called a dependency resolution failure caused by incompatible version constraints.

Network or Cache Issues

Gradle caches downloaded dependencies locally. If a cache entry is corrupted — which can happen after an interrupted download, a forced kill of a build, or a disk issue — Gradle may fail to resolve a file it thinks it already has. Offline mode being accidentally enabled is another culprit.

Local Module or File Dependencies

If your project references a local module (another Gradle subproject) or a local .jar/.aar file, and that path is wrong or the file is missing, Gradle will fail at this step. This is especially common when cloning a project that was developed on a different machine with different absolute file paths hardcoded somewhere.

SDK or Build Tools Version Mismatch

If the Android SDK, build tools, or platform version referenced in your build.gradle isn't installed on the current machine, Gradle can't resolve the necessary Android platform files. This is a common cause when setting up a project on a new development environment.

Key Variables That Determine What's Actually Wrong

The same error message can stem from very different root causes depending on your setup:

Where to Start Investigating 🔍

Rather than a single fix, diagnosing this error means narrowing down which of the above categories applies. A few general approaches that help clarify the source:

• Run ./gradlew dependencies (or gradlew.bat dependencies on Windows) to print the full dependency tree and spot where resolution fails
• Check the full error output — Gradle usually prints which specific dependency it couldn't resolve, and that name is your first clue
• Invalidate caches in Android Studio via File > Invalidate Caches / Restart to rule out local cache corruption
• Check your repository blocks in both settings.gradle (Gradle 7+) and build.gradle to confirm google() and mavenCentral() are present
• Verify installed SDK components in the SDK Manager to confirm required platforms and build tools are present

How Project Setup Affects Outcomes

Two developers hitting the exact same error message may need completely different solutions. A developer on a clean machine cloning from source control is likely missing an SDK component or a local file dependency. A developer who just upgraded their AGP version is more likely dealing with a version conflict. Someone behind a corporate network may need proxy configuration before any resolution works at all.

Projects with Gradle version catalogs, composite builds, or custom artifact repositories add additional layers of resolution logic — meaning more things to check, and more places the process can stall.

The error is specific enough to be actionable, but the resolution path depends entirely on what your dependency graph actually looks like, what's installed locally, and how your project is structured.