What if I have trouble installing an update on my Lumia phone?

• An update package can be several megabytes in size, so it is recommended that you use a Wi-Fi connection. Wi-Fi connection is your phone’s default connection method.
• Before starting the update, make sure your phone has enough battery power, or connect to a charger. If the phone battery level is too low, your phone will also prompt you to charge the battery before starting the update. 
• It is recommended that you create a backup before doing a software update. On the start screen, swipe left to the apps menu, tap Settings > backup.
• Check that your phone is set to the correct time and date. With a wrong date or time, your phone might not be able to access the updates.
• Make enough space on your phone for the update. If necessary, remove some apps or other large items. To check available memory, on the start screen, swipe left to the apps menu, tap Settings > storage check (1.5GB free phone memory recommended). For more tips and tricks, see How to make room on my phone to update it.
• If the update is not successful, your phone remains in its previous software version with data intact. If you get an error code, write it down. With this info, you can check what went wrong at the Microsoft support page.
• If you cannot find a solution to your problem in the info above, you can also try our Discussions community.