I cannot print using my Brother machine on a wireless network (Mac)

I cannot print using my Brother machine on a wireless network (Windows)

Wireless setup is requesting a WPS PIN to complete the setup

I configured the "IP Config" method of the machine to "Auto" to assign an IP address automatically, however it was changed to "Static" unexpectedly. I get an error message that indicates IP address is not unique, or a document is printed out by the machine I didn't expected.

I want to use the Simple Network Configuration capabilities of Apple Mac OS X but I cannot find my printer in the "Print Center", "Printer Setup Utility" or "Default Printer Browser".

I'm using Windows Vista and trying to use a network connected Brother machine. However, I cannot see the machine in the Network Explorer. What should I do?