How to fix error code 921 on Google Play Store

The first thing you need to try to fix the Google Play Store error code 921, is to restart your device. Turn your device off and turn it back on, so that the Google Play Store app, and the entire operating system will be restarted, including all the processes on your device that are part of the operating system or of other apps.

Another way to fix the error code 921 is to log out from your Google account and log back in. The reason why this approach is effective is that it will repair all the "threads" throughout the operating system used by the Google account to have access to Google apps (Youtube, Gmail, Music, and more).

You can log out from your Google account by following the steps below: 

1. Go to Settings, tap on Accounts and backup (or just Accounts); 
   

   
   
   

2. Tap on Accounts and select Google;
   

   
   
   

3. Select the Google account you are logged in with and then tap on Remove Account;
   

   
   
   

4. Restart your Android device;
5. Sign back in to your Google account.

The purpose of the cache and cookies is to allow us a faster experience while using our devices, as we won't have to start all over again when we open apps, i.e. we won't need to log in every time, or configure apps to our liking. Corrupt cache and cookies, however, can do quite the opposite. What needs to be done is to remove those corrupt data manually, and replace them with clean versions, which is done automatically by the operating system. You can do this by wiping the cache partition via the recovery menu.

In order to access the recovery mode and wipe the cache partition, follow these steps: 

1. Power off the device. If you can't do that using the power button, just remove the battery and insert it after 10 seconds.
   
   
2. Press and hold the Volume (+) up and the Power (Sleep/Wake) buttons. Once your device turns on, let go of the buttons.
   * If you use a Samsung device, press the Power (Sleep/Wake), Volume (+) up and Home button.
   
   
3. Press the Volume up or Volume down key to navigate through the options. Highlight the Wipe cache partition then press the Power (Sleep/Wake) key to make the selection.
   
   

   

While good cache and data files can significantly improve the user experience, corrupt data and cache files can cause the Google Play Store error code 921, as well as many other errors. In order to fix this error, you need to clear them. Once they are cleared, they will be automatically replaced with new cache and data.

You can clear the data and cache files of Google Play Store and all the related Google apps by following the steps below: 

1. Go to Settings > Apps/Application Manager;
2. Select Apps/Applications Manager;
   

   
   
   

3. Select Google Play Store from the list and tap on the clear data and clear cache buttons;
4. Select Google Services Framework from the list and tap on the clear data and clear cache buttons;
5. Select Google Play Service from the list and tap on the clear data and clear cache buttons;
6. Select Download Manager and tap on the clear data and clear cache buttons.
   

   
   
   

Here is a video tutorial on where to clear app data and cache files (taken on a Samsung Galaxy device, running on Android OS 8 - steps may vary from one device to another):

It is possible that the Internet connection you are connected to is unstable, or overloaded. If you are connected to a Wi-Fi network, connect to another Wi-Fi network, or mobile data. Also, whenever you switch between connections, close the Google Play Store app through the app switcher (tap on the horizontal or vertical three-line button) and try to download and install the app again.

You can improve your Internet connection by following the tips below:

• Move the router's antennas in different positions;
• Buy a strong router;
• Buy a signal booster (if you live in a house);
• Upgrade your Internet provider plan, to allow for greater download an upload speeds;
• Subscribe to a different, more stable Internet provider if nothing else worked.
  
  

Learn more on how to improve your Internet connection, in the slow Internet guide.

Maybe the current operating system version on your device is the reason for this Google Play error, because it's outdated. The reason is that your operating system version may not be able to understand the instructions provided by the Google's servers, which have been adjusted to meet the latest "trends." Check for an update and update your device's operating system to the latest version.

To update the device's operating system to the latest version, follow the steps below:

If the other solutions didn't work, consider resetting your device to its factory settings, which will remove the corrupted system files from your device and resolve many issues along the way. To reset your device to its factory settings, follow the steps below:

1. Backup your device's data to any cloud storage service (e.g. to Google Drive, Dropbox);
2. Go to Settings, tap on Reset and tap on the factory reset option;
   

   
   
   

Feel free to watch the tutorial below, on how to reset your device (taken on a Samsung Galaxy device, running on Android 8 - the steps described may vary from one device to another):

Note: Make sure that your device is fully charged, before resetting it, to avoid additional complications. Also, do make a backup of your personal files (photos, videos, music, and other documents), so that they are safely stored.