In all Sonicwall UTM Firewall appliances, traffic from the wireless network (WLAN) to the wired network (LAN/DMZ) is blocked by default. However, in certain cases wireless computers may need to access a server or a printer on the LAN/DMZ network segment. This can be accomplished by changing the default Deny rule to an Allow rule.
Procedure:

1. Log in to the Sonicwall management interface�
2. Navigate to the Firewall > Access Rules page
3. Open the WLAN to LAN page.�

4. Click on the configure button on the far right side of the rule.

5. Change the Action from Deny to Allow.

6. Click OK to save the change.

Try to ping a device on the LAN side from a wireless computer and you will be able to get a reply.

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