How to Fix ‘APPLICATION NOT INSTALLED’ Error on Tecno, Infinix, Gionee, saamsung, HTC, Xiaomi and other Android phones - It’s the annoying error message you hate seeing on your Android phone: “Application not installed”. What happened? All you were trying to do was install an Android app. That should be simple.

Receiving this error message is a common problem when downloading APK files. APK stands for Android Application Package, and it used by the Android operating system as the package file format for the installation and allotment of mobile apps.
If for some reason, your Android device is unable to access Google Play, APK files offer another option for installing and downloading mobile apps. APK files are designed exclusively for Android devices.

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How to Fix ‘APPLICATION NOT INSTALLED’ Error on Androids


POSSIBLE CAUSES AND SOLUTIONS

First, it is important to identify the reason the message is being displayed. Knowing the root cause will make finding a solution more accessible.
There are various reasons that could cause this error message to display. Let’s look at these common causes and some ways to resolve them.
Problem: Not enough available storage space. This is a very common reason for the error. The app can’t be installed because there isn’t room for it on the device. If storage is full, no new apps can be downloaded.
Solution: Go through all of your current apps and delete any that you do not use to free up storage space. You can also delete photos, music and videos to free up any additional storage.
Problem: Corruption of the app or the APK file. This is common when an app is downloaded from an unofficial source/outside of Google Play. The app you are trying to install may be already corrupted. It could also be copied from another source, or it may not even be fully available.
Solution: Double check the source you’re using to download the app and ensure it is a reliable source. If you cannot confirm this, it would be better to download the app from a trustworthy source such as Google Play.
Problem: an APK signature or certificate clash. Android operating systems are defaulted to require that all applications be signed when installed. This signature is used to identify the author of the application and to build confidence among applications with the same signature. An app with a valid signature ensures that it is coming from the developers you expected. If you attempt to install an APK from outside the Google Play Store, and use it as an update to an app you currently have, the OS will try to validate the application’s certificate by ensuring it came from the same developers. If the certificate matches, the application will install as desired. If the certificate does not match, it implies the APK has been tampered with and will result in an “Application not installed” error message.
Solution: Ensure you are installing the application from a valid source. Delete any previous versions of the application that you may have on your Android device.
Problem: Incorrect app install location. This is a common reason for the error message. There are certain apps that can only be installed on phone memory. Other apps can be installed on both the phone memory and the SD card. An SD card is a memory card that can be used on Android devices to allow for more space for your photos, games, apps and music. If an app that is only available to be downloaded on the phone memory attempts to install on the SD card, it will result in the error message.
Solution: First you can attempt to reset your device’s app permissions. To do this go to Settings>Apps>All>Menu key>Reset app permissions or reset app preferences. Second, you can change the application installation location to ‘Let the system decide’ or ‘Automatic’.
Problem: Corrupted storage on the phone or SD card. This is likely the most common problem when it comes to issues with applications not being installed. If the storage of your Android device or the SD card is corrupt in any way, no new application can be installed.
Solution: If there is corruption, it is most likely to be your SD card that is corrupted over your phone storage. In this case, you can reformat your SD card. Copy the contents of the memory card to another location as a backup first, and then reformat the card. To format your SD card on your Android device, go to the home screen and tap on Menu>Settings. Proceed to SD & Phone Storage. Tap on “Unmount SD card” and then validate. Follow this by tapping on “Format SD”. Follow the process on the screen to complete the formatting.
Problem: Installation on a mounted SD card. It’s possible that your SD card is mounted on a laptop or another device. If this is the case, the SD card will be seen as not accessible and therefore errors will occur when you attempt to install a new app.
Solution: This is a very simple solution; ensure that your SD card is not connected to any other devices. If it is, disconnect it.
Problem: Temporary operating system errors or app permission errors may also be the cause of this issue.
Solution: In this case, there isn’t a direct go-to solution. It may be as simple as waiting and attempting to install the app later, hoping the temporary glitch has resolved itself.
OTHER OPTIONS TO RESOLVE THE ISSUE

There are a few other options in attempting to resolve the ‘application not installed’ issue if the causes are not any of the above.
As we do with all electronic and technological devices when they give us problems, reboot your phone. You also try to simply shut down the device, remove the battery and reinsert it.
The last solution to resolve the problem is to completely wipe your phone. This is not an ideal option and should only be used as a last resort. You can wipe your device by going to Settings and doing a factory reset. You can also do a total wipe in recovery mode. Again, this option should only be used if you have attempted allof the above and not been successful.
GOODBYE ERROR MESSAGE

Now you are all set for the next time you receive that pesky ‘Application not installed’ error message. Instead of rolling your eyes and throwing your phone in frustration, you can go through all of the causes and solutions in this article. You’ll be sure to resolve the issue quickly and easily.
In some cases, it will be as simple as shutting your phone off and taking out, then reinserting the battery. Or a simple reboot of your phone may do the trick. It may be that you’ve got so many amazing apps, photos and games, that there simply isn’t any remaining storage left on your phone; that’s easy to fix with the deletion of apps you no longer use.
Even if the root cause is more serious and the fix is more laborious, at least you have options of how to resolve the issue now.

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