Canon EOS 80D Instruction Manual page 459

Cautions for Using Eye-Fi Cards
If [Wi-Fi/NFC] under [51: Wireless communication settings] is set to

[Enable], image transfer with an Eye-Fi card is not possible.
If "J" is displayed, an error occurred while retrieving the card

information. Turn the camera's power switch off and on again.
Even if [Eye-Fi trans.] is set to [Disable], it may still transmit a signal. In

hospitals, airports, and other places where wireless transmissions are
prohibited, remove the Eye-Fi card from the camera.
If the image transfer does not function, check the Eye-Fi card and

computer settings. For details, refer to the card's instruction manual.
Depending on the wireless LAN's connection conditions, the image

transfer may take longer or it may be interrupted.
The Eye-Fi card may become hot as it transmits.

The camera's battery power will be consumed faster.

During the image transfer, auto power off will not take effect.

If you insert a wireless LAN card other than an Eye-Fi card, [Eye-Fi

settings] will not appear. Also, the transmission status icon <H> will not
appear.
H Using Eye-Fi Cards
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