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If the same button that is pressed to view or review images does nothing, but when that button is used for some other function that other function works fine, then check:
1. that the memory card is readable e.g. on a computer's card reader
2. that the memory card has actually got pictures stored upon it
3. that new pictures can be stored upon it, at least.
After which, you might want to try a factory settings reset just in case it helps.
After which, yes, you should return the camera to Panasonic UK for warrnaty service repair, if it is less than a year since its purchase date.http://www.panasonic.com/uk/support.html
has at the right, a Contact Us link, and at the left a Locate Service Center link. If you use the Service Center Locater function, then for you the first field selection is 'Visual', and the second is 'Digital Still Camera'.
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