I assume that you can review previously taken photos, that are on your memory card, on the LCD screen.
That would indicate that the CCD sensor is not functioning.
There are several reports of this type of failure.
It requires the replacement of the CCD sensor.
You should contact Canon Service.
It is faster to contact them by phone that using email.
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My Canon S2 is about 2 years old. Lately, I have no image in the viewfinder, so I can't take pictures. I press display, but the viewing image is still not there. Is this a known problem? Do I have to send it to Canon to be fixed?

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