Canon EOS 5D Mark IV Instruction Manual page 153

What to check on the proxy server
Is the power of the proxy server on?

Turn on the proxy server.

Is the proxy server working correctly?

Check the proxy server settings to make sure it is working correctly

as a proxy server.
If applicable, ask your network administrator for the proxy server's

address setting and port number, then enter them on the camera.
What to check on the network as a whole
Does your network include a router or similar device that

serves as a gateway?
If applicable, ask your network administrator for the network

gateway address and enter it on the camera.
Make sure that the gateway address setting is correctly entered on

all network devices, including the camera.
Responding to Error Messages 21 - 24
Check also the following points when responding to errors numbered 21 -
24.
Are the camera and the access point set to use the same encryption
key for authentication?

This error occurs if the encryption keys do not match when the authentication
method for encryption is set to [Open system]. The setting is case-sensitive,
so check upper- and lower-case characters. Make sure that the correct
encryption key for authentication is entered on the camera (p.71).
Responding to Error Messages
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