Then if that fails, it needs service. This answer is all over the web. You can find it with this search.
https://www.google.com/search?q=hdd+format+eror+e%3A+31%3A00
Bob
Problem camera HDR-xr350ve
I turn on the camera and she writes me an error
hdd format eror e: 31:00
What do I do to fix it?

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