Here are some general troubleshooting steps you may try in isolating the issue.
Make sure the USB ports on both the camera and computer are not dusty or dirty.
Make sure that the battery is fully charged.
Make sure that the USB cable is connected properly to the camera's and computer's USB port. (Note: USB hubs are not recommended for use.)
Make sure that the memory card is properly inserted into and read by the camera.
Check if the USB port is working by trying other USB devices.
Turn off the camera, remove the battery and allow it to rest for 30 seconds. Afterwards, reinsert the battery and attempt to establish connection.
Try to restart the computer.
Try another USB cable.
Please provide more information about your camera's model number, you computer and its operating system, and the type of memory card you are using. This will help us understand how we could troubleshoot the issue further.
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