I assume you are trying to take a video.
See if the SDHC will work when taking a still picture.
If it will, the card may not be fast enough for video.
A Class speed of 6 or higher is required for video.
The card must be formatted by the camera before using the card.
Does the camera work with a SDXC card?
.......
My Panasonic DMC FH27 camera which I love does not recognize when there's a memory card in it. The camera is known to use SDXC cards and currently I have an SDHC card which is compatible. I have used other compatible cards thinking one may be corrupt, but with same results. I've used new cards formatted and unformatted to no avail. The camera says "pictures will be recorded to built in memory." And I have two Lumix cameras with the same issue/problem, different model.

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