Why are my apps suddenly stopped working everytime i use it??

[AC Question]

I bought a samsung galaxy duos from SA. but every time I use it always says "Unfortunately settings has stopped working", not only in settings but also to other apps. ex. "Google chrome has stopped working", "samsung galaxy ui. stop working"... etc. I've tried a lot of things but didn't work. please heeeelp!!!

 

[B. Diddy]

Welcome to Android Central! Try booting into Safe Mode, which temporarily disables all 3rd party apps. The steps for your Duos will probably the same as those for the S5: https://support.t-mobile.com/docs/DOC-10696

If the problem disappears in Safe Mode, then something you installed is causing the problem. You may have to uninstall apps one by one until the problem disappears. If the problem persists in Safe Mode, then it's more likely to be a hardware or firmware problem.