Back up texts and photos in Windows 10 Mobile
Turn on these options and you’ll be able to get your texts and photos back on a Windows 10 Mobile phone if you reset, update or replace it.
Go to Settings > System > Messaging and turn on Text backup.
Go to OneDrive > the Menu icon (three horizontal lines in the top left corner) > Settings > Camera upload, then turn it on.
Pictures that you take or save on your phone will now be automatically uploaded to OneDrive.
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Same solution already provided from Microsoft
This setting is on but still does not update automatically, why
Re: Message backup. I went to settings-system-messaging and there was no text backup setting to turn on
How could i get my back up sms??????