The upload stopped before it was ready

There are several possible reasons why uploading from the Google Photos Backup / Desktop Uploader app stopped:
  1. The uploader application needs a "soft reset": reboot your computer.
  2. The uploader application needs a "hard reset". Follow the following steps:
    1. Stop "Google photos desktop uploader": Right-click the system tray icon + "Quit"
    2. Delete the following folder:
      1. On Windows: %localappdata%\Google\Google Photos Backup\     (copy/paste the path to the address bar in "Windows explorer")
      2. On Mac: ~/Library/Application Support/Google/Google Photos Backup/
    3. Start "Google photos desktop uploader" again (it should be somewhere in your start menu, or if you reboot your computer it will restart as well)
    4. It will recheck all pictures again, but shouldn't re-upload the pictures again.
  3. It might be a temporary problem on the Google servers.
  4. You might have reached the fair use policy for bandwidth usage for your account. If you upload or download "abnormal" amounts of photos and/or videos in a relatively short time span, your Google account can get "blacklisted." This can take up to a month to be cleared. If you have this problem, you won't be able to upload new photos on photos.google.com either, so this is a good test to possibly eliminate that this is the problem. See solutions here:
    Not able to upload any photos anymore
  5. Photos and videos aren't backing up, more tips here: https://support.google.com/photos/answer/6174018?hl=en
    1. Upload requirements:
      1. Photos can't exceed 75MB or 100 megapixels
      2. Videos can't exceed 10GB

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