App Not Installed Error on Android: 9 Causes and Fixes
Image: Beamish4, CC BY-SA 4.0, via Wikimedia Commons
The message App not installed appears when Android refuses to complete an installation, and it rarely says why. The cause is usually one of a small number of things. Work through the list below from top to bottom, because the early items are the quickest to check.
1. Not enough free storage
The installer needs room to unpack the app. Free several gigabytes and try again. This guide lists safe ways to do it.
2. The download is incomplete or corrupted
If the connection dropped, the file may be damaged. Delete it and download it again, ideally on a stable connection. Compare the file size with the listing.
3. A signature mismatch with the installed version
Android only lets an update install over an existing app if both were signed with the same key. If you installed the app from Google Play and now try an APK signed by someone else, the install fails. The only fix is to uninstall the current copy first, which deletes local app data, so back up anything you need. A mismatch can also mean the new file was tampered with, so check the source (see our safety checklist).
4. You are installing an older version over a newer one
Android blocks downgrades because older versions may not understand newer data. Uninstall the current version first, or keep the version you already have.
5. The app needs a newer Android version
If the app requires a higher Android version than yours, it will not install. Check the Requires Android line and your own version as described in this guide. Newer Android releases also refuse apps built for very old Android versions.
6. The file does not match your processor
An APK built only for one processor type fails on another. Download the variant that matches your phone, or a universal build.
7. You tapped a bundle, not an APK
XAPK, APKM and APKS files and split APK sets need a proper installer. See our file type guide.
8. Play Protect or a security setting is blocking it
Play Protect may stop an app it considers risky. Read the message instead of dismissing it. If you do trust the file you can continue from the prompt, but never switch protection off for a file you cannot verify. On phones with parental controls, a work profile or a managed account, an administrator may block installs from outside the store.
9. Install permission or file location problems
Make sure the browser or file manager you used has permission to install unknown apps (see step 1 of the install guide). Copy the file to internal storage before installing if you are opening it from an SD card or a cloud folder.
Find the exact error code with a computer
If none of the above works, connect the phone with USB debugging on and run adb install app.apk. The terminal prints a precise error:
| Error | Meaning | Fix |
|---|---|---|
| INSTALL_FAILED_INSUFFICIENT_STORAGE | Not enough space | Free up storage |
| INSTALL_FAILED_UPDATE_INCOMPATIBLE | Signature differs from the installed copy | Uninstall the old version first |
| INSTALL_FAILED_VERSION_DOWNGRADE | File is older than the installed version | Uninstall it, or use a newer file |
| INSTALL_FAILED_OLDER_SDK | App needs a newer Android | Use a compatible version |
| INSTALL_FAILED_NO_MATCHING_ABIS | Wrong processor type | Download the right build |
| INSTALL_PARSE_FAILED_NOT_APK | File is not a valid APK | Download it again and check the file type |
| INSTALL_PARSE_FAILED_NO_CERTIFICATES | Package is unsigned or damaged | Download it again from the source |
Keep your data when you reinstall
Uninstalling removes local app data. Before you do it, check whether the app syncs to an account or has its own backup option. Android’s automatic backup can restore some app data when you reinstall from Google Play, but it does not cover everything. If you only need to replace an app with a newer build signed by the same developer, installing over the top with adb install -r keeps its data.
Still stuck?
Restart the phone, then clear the cache of the system package installer (Settings, Apps, show system apps, Package installer, Storage, Clear cache) and try again. If the app is on Google Play, installing from there avoids most of these problems. You can also browse our apps and games listings, which link to the official Play pages.
How to avoid the error next time
- Check the Requires Android line and your processor type before downloading.
- Keep several gigabytes of storage free.
- Download from one trusted source and compare the file size and version with the listing.
- Do not mix sources for the same app, because a different signing key blocks updates.
- Back up important app data before you replace an app.
Frequently asked questions
Why does the error appear only on some phones?
Phones differ in Android version, processor type, storage and security settings, so a file that installs on one can fail on another.
Will uninstalling the app delete my progress?
Local data is removed on uninstall. Progress saved to an account, such as an in-app login or Google Play Games, comes back when you sign in again. Check what the app saves before you uninstall.
Is it safe to turn off Play Protect to get past the error?
No. If Play Protect is blocking a file, treat that as a warning and verify the file first. Turning protection off also removes a useful safety net for every other app.
The error says the package appears to be invalid. What does it mean?
The file is probably damaged, incomplete or not a real APK. Download it again, make sure it ends in .apk and compare its size with the listing.