How to Allow Install Unknown Apps on Samsung Galaxy (One UI)

Samsung Galaxy phones block app installs from outside the Galaxy Store and Google Play by default. That is a sensible starting point. If you want to install an APK you downloaded yourself, you first need to give one specific app, usually your file manager or browser, permission to install other apps.

This guide walks through the steps on One UI, Samsung's version of Android. Menu names shift a little between One UI versions and regions, so if a label on your phone is slightly different, look for the closest match.

How the permission works

On modern Android, there is no single "unknown sources" switch for the whole phone any more. Instead, the permission is granted per app. If you allow My Files to install apps, Chrome and Samsung Internet still cannot. That design limits the damage if one app is misused, and it is why you should only allow the app you are actually going to use.

Method 1: Allow it from the install prompt

This is the quickest route and works on most Galaxy phones.

1. Open My Files (or the browser you downloaded with) and tap the APK file.
2. A message appears saying your phone is not allowed to install unknown apps from this source. Tap Settings.
3. Switch on Allow from this source (on some versions, Allow permission).
4. Press back. The install screen returns; tap Install.

Method 2: Allow it from Settings

Use this if you prefer to set the permission first, or if you dismissed the prompt.

1. Open Settings and tap Apps.
2. Tap the three-dot menu (⋮) in the top corner. On some versions it is a sort or filter icon instead, with the menu next to it.
3. Tap Special access.
4. Tap Install unknown apps.
5. Choose the app you will install from, for example My Files, Chrome or Samsung Internet.
6. Switch on Allow from this source.

The list shows every app that has asked for this permission, and which ones currently have it. It is worth scanning while you are there.

If Auto Blocker is switched on

Recent One UI versions include Auto Blocker, a Samsung security feature that, among other things, blocks installs from unauthorised sources. You will find it under Settings → Security and privacy → Auto Blocker. When it is on, allowing an app as a source is not enough, and the install will still be blocked.

Auto Blocker is a deliberate protection, so treat it as a question rather than an obstacle. Ask whether you really need this app from outside the store, and whether you can verify the file. If you decide to go ahead, remember to switch Auto Blocker back on as soon as the install is complete.

Before you tap Install

A few checks take only a minute:

• Confirm the source. Download from the developer's own channel or a site that clearly identifies the file, its version and its size.
• Check the file name and size against what the download page says.
• Let Play Protect scan it if you are offered the option, and read any warning rather than dismissing it.
• Look at the permissions the app asks for on first launch, and deny anything that does not fit what the app does.

Turn the permission off afterwards

Once the app is installed, the source app no longer needs the permission. Leaving it on means any file that browser or file manager opens later could start an install prompt.

1. Go back to Settings → Apps → ⋮ → Special access → Install unknown apps.
2. Tap the app you allowed.
3. Switch Allow from this source off.

Turning it off does not remove or break the app you installed. You only need to allow it again when you install an update from a new APK file. Apps that update themselves in-app will ask for their own permission, which you can grant and revoke in the same list.

Key takeaways

• On Samsung, "install unknown apps" is granted per app, not for the whole phone.
• The path is Settings → Apps → ⋮ → Special access → Install unknown apps, or tap Settings on the install prompt.
• If Auto Blocker is on, installs from outside the stores stay blocked; switch it back on after any exception.
• Revoke the permission once you are done. Your installed app keeps working.