Nokia Lumia 820 - Why am I getting the error code 0x80181548 when trying to perform a device backup on my Nokia Lumia phone?

This error message may occur in the following cases:

  1. You have an account (other than your Microsoft account) stuck in attention needed status in the account list. To resolve the issue, select Settings > email + accounts and look for highlighted account with attention needed.  
  2. You have chosen a wallpaper picture over 1MB in size (though the device will let you utilized a wallpaper up to 2MB, the backup service is only configured to enable 1MB photo’s). Changing the wallpaper to one of the default images will likely resolve the issue for the backup process. To change the wallpaper, select Settings > lock screen > change photo and choose one of the default images. If you want to use a large wallpaper you may need to manually perform a backup, since the automated backup may not work with the large format wallpaper. Do the following: - Change the wallpaper as described above. - Perform backup manually by selecting Settings > backup > app list + settings > back up now.   - Once the backup or update is complete you can once again utilize your customized wallpaper.