Android install errors, explained

Android tends to report a failed install as “App not installed” and leave it there. Each page below covers one real cause: what it means, why the system does it, and what actually fixes it.

• Install failed: the existing app is signed with a different certificate

  INSTALL_FAILED_UPDATE_INCOMPATIBLE

  The app you are installing was signed with a different key than the copy already on the device. Android will not treat it as an update.

• Install failed: cannot downgrade to an older version

  INSTALL_FAILED_VERSION_DOWNGRADE

  The version you are installing is older than the one already installed, and Android refuses downgrades unless the installer explicitly asks for one.

• Install failed: the package is already installed

  INSTALL_FAILED_ALREADY_EXISTS

  An app with the same package name is on the device and the install was not told it is allowed to replace it.

• There was a problem parsing the package

  Android could not read the file as a valid package. Usually the file is incomplete, or it is not the kind of package the system installer can open on its own.

• Installs keep failing on Xiaomi, Redmi or POCO

  MIUI and HyperOS ship a setting called MIUI optimization that blocks third-party installs, usually without explaining why.

• Install failed: no matching CPU architecture

  INSTALL_FAILED_NO_MATCHING_ABIS

  The package contains native code, but not for your device's CPU architecture.

• Install failed: not enough storage

  INSTALL_FAILED_INSUFFICIENT_STORAGE

  The device does not have room for the app — often even when the free-space figure looks like it should be enough.

• Install failed: the app targets an old Android version

  INSTALL_FAILED_DEPRECATED_SDK_VERSION

  Android 14 and later refuse to install apps that target very old API levels.

• Install failed: the package is invalid

  INSTALL_FAILED_INVALID_APK

  The archive is malformed, unsigned, or a split bundle is missing a part it needs.

• App not installed

  Android's catch-all failure message. It has no single cause — the useful information is in what the app was and what changed.