First, to set a good reference point, reset the camera using the attached instructions
Next, in auto, the one thing that even experienced photographers miss is that a single small spot or smudge on the lens can cause the problem that you are having. Carefully clean the lenses again and look for any dust or fingerprints. Depending on the environment that you are shooting in, a haze can build up on the lens and cause incorrect readings and the shutter will not release until accurate focus has been achieved Go back to Auto Focus and try a few shots. Please let me know the result.
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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