If you are trying to use 4gb (SDHC) or larger capacity card, they are by design, not compatible with your camera. The Kodak P880 , made in 2005 / 2006, can use cards up to a 1GB capacity. The larger cards have a different file structure.and will not function correctly with cameras made before 2007. A 1GB card is the highest capacity that this camera can use. See page 81 of the manual page attached. 2gb SD cards will work but I have found them to be fairly unreliable in these older cameras. You can get a 1gb card at the link below.
Please keep in mind that my diagnosis & solutions provided are directly dependent on the accuracy of your description of the problem. As with any "do it yourself" fixes, success is a "team effort", since I can't see or touch the camera, and relies on the customer's manual dexterity and ability to follow the instructions well.
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If you have not already done so, remove any card and go to the setup menu and perform a reset. Re-install the card and try to format it. Please let me know the result.