First, put the mode dial to "P". Now you can use the menu to do a "CUSTOM RESET" (see p.118 of the printed manual).
The same thing happened to me. One day when I went to take pictures - all of a sudden all of them were very obviously tinted blue. I finally fixed the problem by checking the white balance. It was somehow set to something weird - and I set it back on AUTO. Setting the white balance is addressed on page 87 of the camera manual.
Check out the Full Manaal- which is a PDF file on the software disk. If nothing there check out customer support.
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