Canon EOS 6D Instruction Manual page 369

Troubleshooting Guide
Image Transfer Problems
I cannot transfer images to a computer.
Install the provided software (EOS Solution Disk CD-ROM)
on the computer (p.393).
Check that EOS Utility's top screen is displayed.
Under the [53] tab, if [Wi-Fi] is set to [Enable], the camera cannot
connect to a computer. Set [Wi-Fi] to [Disable], then connect the
camera to the computer with an interface cable.
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