If your OnePlus Open's Settings app keeps closing or crashing, it's usually a temporary software hiccup. The good news is you can almost always fix it yourself without losing any data. I'd start with a simple restart, as that clears out most temporary glitches right away.
Restart Your OnePlus Open
Press and hold the power button on the right side of the phone. When the power menu appears, tap "Restart." If the Settings app is crashing so badly you can't even get to that menu, you can force a restart instead.
Just press and hold the power button for about 10 seconds. Keep holding it until you see the screen go black and the OnePlus logo reappear. This is a soft reset that doesn't erase any of your personal files or settings.
Clear the Settings App Cache
Corrupted temporary files are a common culprit for app crashes. Clearing the cache for the Settings app forces it to rebuild these files from scratch, which often solves the problem.
Go to Settings > Apps > App management. Find and tap on the "Settings" app in the list. Then, tap on Storage usage and select Clear cache. This only removes temporary data, so you won't lose any of your actual phone settings.
Force Stop the Settings App
If the app is stuck in a bad state, forcing it to stop and restart can clear the issue. This is a quick step you can do right after clearing the cache.
While still in the Settings app's info page (under Apps > App management > Settings), tap the Force stop button. Confirm the action if prompted. The app will close completely and restart the next time you need to use it.
Check for a System Update
OnePlus frequently releases OxygenOS updates that include bug fixes for issues just like this. An outdated system can sometimes cause conflicts with core apps.
Open Settings and go to About device > OxygenOS version. Tap on the icon with three dots in the top right, then select Download now. If an update is available, follow the prompts to install it. Your phone will restart, and the new software might resolve the crashing.
Manage Google Play Services
Google Play Services works in the background to help system apps communicate properly. If it has an issue, it can cause unexpected crashes in apps like Settings.
Head to Settings > Apps > App management and find "Google Play Services" in the list. Tap on it, then go to Storage usage. First, tap Clear cache. If the problem continues, you can go back and tap Manage storage > Clear all data. Don't worry, this will reset the service but it will rebuild its data automatically.
Boot Into Safe Mode
This helps you figure out if a recently downloaded third-party app is causing the conflict. Safe mode temporarily disables all apps you've installed from the Play Store.
Press and hold the power button until the power off menu appears. Then, press and hold the "Power off" text on the screen. A prompt will ask if you want to reboot to safe mode. Tap "OK." If Settings works fine in safe mode, you know a third-party app is the problem. Restart your phone normally to exit safe mode and try uninstalling apps you installed just before the trouble started.
Reset App Preferences
This is a useful middle step that resets all your app permissions, default apps, and background data restrictions without deleting any app data. It can fix issues caused by a misconfigured permission.
Go to Settings > Apps > App management. Tap the three-dot menu in the top right and select Reset app preferences. Confirm the reset. You'll just need to re-grant permissions to apps the next time you use them.
Perform a Factory Reset
If nothing else has worked, a factory reset will return your OnePlus Open to its original software state. This will erase all your data, so it's absolutely crucial to back up everything important first using Google One or by manually transferring files to a computer.
Once you're backed up, go to Settings > Additional settings > Back up and reset. Tap on Erase all data (factory reset). You may need to enter your lock screen password. Follow the final prompts to begin the reset. After it completes, you can set up the phone as new or restore your backup.
