Bypassing the Firewall/Router

I’m having trouble going directly to my switch from my router. The path goes from the demarc to the ISP’s router, (Cisco IAD 2400 series), to a small router/firewall, (Linksys BEFSX41), we use for the firewall part, then to the switch. No problems there. When I plug from the ISP’s router into the switch,(HP Procurve 1410 24G), plugging directly into the front panel where the firewall/router was connected, I lose the internet.

Is something staring me in the face, that I’m going to be embarrassed about missing? If so, please tell me what it is.

Thanks,
Stephen