SonicWall disconnects WiFi connection

[Paresh]

Hi

Modem wifi works ok when no other device connected. But when I connect Sonicwall firewall to ethernet port (out of 4), modem wifi stops working. It shows as connected but none of the sites or internet working

Thanks

Paresh

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[Datalink]

@Paresh, any chance that the Sonic Firewall has a manually set IP range, which might conflict with the modem's IP range.  Are you running the firewall with it's firewall up and running, intending to create a protected zone inside of the modem's firewall and IP address range?  Or, is the intent to use the Sonic Firewall as an Access Point?

Can you also have a look at the back of the modem, specifically at the LED for the port that is connected to the Sonic Firewall.  It should be flashing amber, indicating a 1 Gb/s interconnect with the Sonic Firewall.  Flashing green indicates a 10/100 Mb/s interconnect rate.