Check the flash mode that your camera is set to. The flash modes are: Auto, Red-Eye Reduction, Forced Flash, No Flash, Slow Synchro, and Red-Eye plus Slow Synchro. You might have the flash mode set such that your camera detects that the lighting doesn't require the flash mode selected. You can try manually overriding the flash mode by pressing left on the circle function button next to the LCD view screen. If you are still unable to manually turn the flash on, try changing the shooting mode with the mode select dial on top of the camera, then if necessary repeat the flash override step mentioned above. Repeat until successful. There is also the possibility that the flash is malfunctioning, but that is less likely than a setting issue. Let me know how you make out.
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Check the flash mode that your camera is set to. The flash modes are: Auto, Red-Eye Reduction, Forced Flash, No Flash, Slow Synchro, and Red-Eye plus Slow Synchro. You might have the flash mode set such that your camera detects that the lighting doesn't require the flash mode selected. You can try manually overriding the flash mode by pressing left on the circle function button next to the LCD view screen. If you are still unable to manually turn the flash on, try changing the shooting mode with the mode select dial on top of the camera, then if necessary repeat the flash override step mentioned above. Repeat until successful. There is also the possibility that the flash is malfunctioning, but that is less likely than a setting issue. Let me know how you make out.