The most common problem that users experience with the Google Play Store on Android devices is that it stops working on launch, or when an app is downloading. Usually the user will be shown an error message with a code when this happens.
One common error code is DF-BPA-09, which is also displayed as Error Processing Purchase. Other common errors include Error 495 (a problem when apps are being downloaded or updated), Error 941 (when an interruption occurs when an app is being updated) and Error 504 (an error that prevents apps from being downloaded).
There are a number of steps that users can take when they encounter such errors. The first is to try clearing the cache from the Google Play Store app. Deleting the Google Play Store data can also help. If this does not work, the user can look at the Google Play Store updates. If an update was applied recently, and the app started causing problems since that update, the update can be uninstalled.
If all this does not work, the user should go to Google Play Services and clear the cache in that app. It is also worthwhile checking to make sure the Download Manager is activated as the Google Play app will give errors if it is not.
If the app still does not work, the user can try removing the Google account from the device and then adding it again, or restoring the device to its factory settings.