Canon EOS REBEL T7I Wi-Fi (Wireless Communication) Function Instruction Manual page 140

Responding to Error Messages
21: No address assigned by DHCP server
What to check on the camera
On the camera, IP address is set to [Auto setting]. Is this the

correct setting?
If no DHCP server is used, specify the settings after setting the IP

address to [Manual setting] on the camera (p.161).
What to check on the DHCP server
Is the power of the DHCP server on?

Turn on the DHCP server.

Are there enough addresses for assignment by the DHCP

server?
Increase the number of addresses assigned by the DHCP server.

Remove devices assigned addresses by the DHCP server from

the network to reduce the number of addresses in use.
Is the DHCP server working correctly?

 Check the DHCP server settings to make sure it is working
correctly as a DHCP server.
 If applicable, ask your network administrator to ensure the DHCP
server is available.
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