Duplicate class found in modules

What this error means

Two dependencies include the same Java or Kotlin classes — usually different Kotlin standard library versions pulled in by plugins.

Why it happens

Two dependencies on the release classpath ship the same classes. Plugin versions that pull different Kotlin standard-library artifacts are the common case.

The message tools print

Duplicate class kotlin.collections.jdk8.CollectionsJDK8Kt found in modules kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)

How to fix it

1. Update the plugins involved so they agree on Kotlin.
2. Or align Kotlin by adding the Kotlin BOM (org.jetbrains.kotlin:kotlin-bom, with your Kotlin version) as a platform dependency in android/app/build.gradle.
3. Sync and build again.

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Other Android build errors

• Android SDK location not found
• Android Gradle plugin requires Java 17 to run
• :capacitor-android project could not be found
• Android resource linking failed
• Keystore was tampered with, or password was incorrect
• Could not resolve all files for configuration