To find out the cause of this problem, first of all boot your phone to Safe Mode. Then it will clear to you whether “Unfortunately Settings has stopped working” problem on Samsung Galaxy S4 is occurring because of any third party apps or pre-installed apps. When your Galaxy S4 is in Safe Mode, open Settings menu and check whether you get the same error message or not. To boot Galaxy s4 in safe mode,

>Hold the power button for 2 secs

>Confirm shut down

>While the phone is booting up, keep pressing the menu soft key , which is found immediately left to the home button

>Wait, keep pressing

If you see that “Unfortunately Settings has stopped working” problem on Samsung Galaxy S4 is not occurring in Safe Mode, then a third party app is causing the problem. So, you have to find out that app and then uninstall it to get rid of such problem.

Open settings from safe mode > More> Application manger >all apps

Find the culprit that’s causing the error. Uninstall , clear data or data cache of that application. Any suspicious application that you have downloaded recently, large or suspicious apps that you think is causing “Unfortunately Settings has stopped working”

But if you see that the error message still occurring when the Galaxy S4 is in Safe Mode also, then the problem is occurring either because of the Application Manager or the Settings app. In such case the only option to do is Factory reset. But doing Factory reset removes all your phone’s data, so before proceed with the Factory Reset, back up all your data.

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