First, remove the CF memory card and try to power the camera up. If the camera functions properly, let me know, if not please continue.
Next, try a hard reset on the camera by removing the main battery, memory card, and the date battery using the information on page 235 of the manual or see attached photo. Once these have been removed, turn the camera to "ON" and allow it to sit for ten minutes. Turn the camera to "OFF", reinstall both batteries and the memory card and try it out. Please let me know the result.
If you do not have the manual handy you can download a PDF copy at the link below. Copy and paste the link into your browser
If the hard reset does not restore functionality, use a flashlight and magnifier to look into the card slot to make sure that all of the pins are straight. A single bent pin will cause the problem that you are experiencing. Unless you possess exceptional skill this issue is not user repairable and will require professional service to replace the entire connector.
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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