Camera screen says "card not initialized"

• turn off you camera and remove the memory card
• reinsert the card and turn on your camera
• re-format the card (low level) using your camera . / or under menu search for format or initialize

May be you inserted a memory card formatted with your PC. Format the memory card using the Format function in the camera menu. Format function can be found in the setup menu of the camera.
If this does not work, try replacing the memory card.

Had you ever initialized (formatted) the card, especially when you first got it? If not, an unformatted card will work fine initially, but almost always corrupts with time after many pictures are added. To prevent this issue permanently, you should always format a new card. But note formatting will erase the card! If you haven't saved your pictures yet, and you're having trouble locating them on the card with your computer, see this article. After you've recovered and saved your photos, format the card IN THE CAMERA using the camera format feature (look for it in its menus). This will rejuvenate the card, and prevent this from happening again.

Without knowing the camera make and model I can only suggest you check your owners manual on how to format your memory card, your manual may also call it initialize.
I'm also going to include a diagram that shows the SD sliding lock, if this lock is in the lock position a whole sea of problems can "pop" up. the lock function is there top protect pictures or files on the card from being deleted by mistake. However sometimes these annoying little trouble makers get pulled down into the lock position.
Here is the diagram. Remember check the lock and then format/initialize your memory card also after each time you download your images from the camera or the optional card reader you must format the memory card to have the camera properly function with the memory card.

Hope this helps have fun with your camera

Is there a format option on the camera?

see if there is a format highlight in menu of camera-this will format card to camera and should make it compatible-format will delete all data from card!

go into settings of your digi cam and use the format option , thats should solve your problem

What type of xD card did you buy?  It needs to be a plain xD card with no letters before the file size or a type "M" card.  For type "M" you will need to upgrade the camera's firmware.
http://www.fujifilm.com/products/digital/download/a330/fupd.html

This type of camera can't use type "H" cards, so cards like "H512mb" aren't going to work.
To initialize a card choose Menu. Arrow over to "Set", then arrow up to choose "Set-up". On screen "1" of the Set-up, arrow down to choose "Format".
This will ask you to erase all the images from the card, and format it.
Just today I upgraded my camera firmware to accept a type "M" card, initialized the type "M" card after that - and now it's working fine!  
Reply back if you need more help. -Kelly.

Format the card in the Camera- read your manual

on pc, try using the utility [format] when card found under "My Computer"