Legacy Products
The resources associated with these products have ceased their development and are no longer supported.
D-Link Systems, Inc. recommends retiring these products and replacing them with products that receive firmware updates.
What does it mean if I see a Default_Access_Rule drop notice in the log message?

The traffic is dropped by the Default_Access_Rule which means that the source network is not routed on the lan interface.

Set Section Rules/Access to allow the dropped network xxx.xxx.x.x/24 so the system will accept it as a sender address.