I am going to assume that you are in Europe, UK, or Canada as the 3945 does not appear to be sold in the USA.
I am also going to assume that it is a new camera, since it is not even listed on the Vivitar website.
That camera may have some internal memory as well as a memory card. If that is true, try using the internal memory to determine if the problem is the card or the camera.
The only other way, is to buy a new memory card and see if the camera reports errors with the new memory card.
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It sounds like the type of problem that happens when you have not formatted the card with the camera.
If you fail to format a new card with the camera, many times the card will appear to fail ... several weeks/months later.
The only way to recover such a card is with a card reader. Card readers are available at WalMart, Staples, and any camera store. If you have Windows XP, you don't even have to install drivers for the card reader (which uses yours USB).
If you put your SD card in the card reader, it will appear to your computer to be another hard drive. You can use Windows Explorer to look at the contents of the card. You should download to the computer, any photo files you find. Then delete all files and folders on the card.
Put the card back in the camera and the camera will probably see it as empty and with no errors. Do not take any photos yet.
Check the camera users guide and find out how to format the memory card with the camera.....and then format the card.
It should then be OK.
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If you find your camera to be defective, contact Vivitar. Most digital cameras have a one year warranty.
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I bought a vivitar camera (vivicam 3945s) six months ago. However, a week ago, when I took a picture and turned to the "image playback" mode to view my picture, the screen said "card error". The orange light also flashed. I tried to format the SD card, but that didn't work. After then, I cannot take any pictures, nor load the pictures on the computer. Do you guys think it's the camera's problem? Or is it the SD card's problem? What should I do? Thanks for your help.

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