Apps won't install or update after I cleared files and data My phone is a mess right now. I cleared some files and data. Now, my Play Store stopped functioning. All my apps won't give notifications anymore. What should I do to fix this huge problem? I just uninstalled all the apps, and they won't let me install or update them again.
Have you tried doing a factory reset? In my Samsung Galaxy S4, it's in: System settings &gt; Acceounts &gt; Backup and reset &gt; Factory data reset. See if you can find something similar to your phone.

WARNING: You will lose all your data when you do a factory reset. But since you uninstalled all your apps, it shouldn't be any problem / issue.