Delta Executor "App Not Installed" on Android
Android shows "App not installed: package appears to be invalid" and the APK refuses to go on. It is nearly always one of five things, and none of them require a different phone.
An older Delta is still on the device
Android refuses to install an APK over an existing app when the signatures do not match — and builds from different sources are signed differently. The old copy does not have to be visible or working for this to happen.
- Open Settings → Apps and search for Delta.
- Uninstall every copy you find, including ones you thought were gone.
- Restart the phone.
- Install the new APK.
If you have installed Delta from more than one site before, this is very likely your cause.
Play Protect is blocking it
Google Play Protect scans sideloaded APKs and will block an executor. It sometimes reports the failure as an install error rather than saying it blocked anything, which is why this one is confusing.
- Open the Play Store, tap your profile picture.
- Go to Play Protect → Settings (the gear icon).
- Turn off Scan apps with Play Protect.
- Install the APK, then turn the setting back on afterwards.
Unknown sources is not enabled for your browser
Modern Android grants install permission per app, not globally. Enabling it for Chrome does nothing if you downloaded the file in a different browser or a file manager.
- Go to Settings → Apps → Special app access.
- Choose Install unknown apps.
- Find the app you are installing from — your browser or file manager.
- Turn on Allow from this source.
The download is incomplete or corrupt
The Delta APK is a large file. A dropped connection mid-download produces a file that looks complete in your downloads list but fails the package check.
Delete the APK, clear your browser's download cache, and download it again on a stable connection. Check the file size against what the Android page lists — a file noticeably smaller than expected never finished.
Not enough free storage causes the same symptom. You need meaningfully more free space than the APK size, because Android unpacks it during install.
The file is not what it claims to be
If nothing above worked, consider that the file itself is wrong. Cloned Delta sites serve renamed installers, wrappers and outright junk.
- Check it is genuinely an
.apk, not an.xapk,.zipor.exe. - Compare the file size against the published release.
- Scan it before installing — see how to read the scan.
- If the download came with a "you must install this other app first" step, delete it.
Other Android messages you might see
| Message | Cause | Fix |
|---|---|---|
| App not installed: package appears to be invalid | Corrupt file, or signature clash with an old copy | Sections 1 and 4 |
| There was a problem parsing the package | Incomplete download or wrong Android version | Section 4 |
| Blocked by Play Protect | Play Protect scanning | Section 2 |
| Installation blocked for security | Unknown sources off for that app | Section 3 |
| Roblox Upgrade: your version of Roblox is out of date | Roblox client, not Delta | Update Roblox from the Play Store |
The last one is worth calling out. That popup is Roblox telling you the game is out of date — it has nothing to do with the APK you just installed. Update Roblox and it goes away.