The lack of getting the menu up is a good clue the product needs repair. After you work though this you can read other folk's posts about power off, battery and such removed and a hard slap. It's not anything a tech will suggest but there is a good reason why it can work. I won't suggest it as it can do more harm than good but with service rates being pretty high you can read what others have to say about it.
Bob
My camcorder suddenly stopped working and will not record photos or video. I am able to view photos and video that are stored on the hard drive. I cannot bring up the menu screen on the display which I assume is related to the overall issue. Does anyone have any ideas of a solution other than sending the unit to Panasonic?

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