Using AE as ethernet wires storage

[Nbd508]

So my current network setup has been a ISP provided router that is wired to an AirportExtreme (2tb)   It's accessible over the network from my devices and also supplies my GUEST network for the house.

I am upgrading to gigbit service next week and replacing the ISP router with my own.  I want to use the AE as a direct connection to my computer rather than a router or access point. 
I currently can use a Standard or Cross (cat6) cable to connect to my Macbook and the AE shows up, I can get files in and out.  However when I plug into the Second port on my MOBO (gigabitnetworkport)  The network connection shows "unidentified network" and the "disk" is not showing up anywhere.   I tried setting 192.168.200.1 for the AE ip  and manually entering that for the IPV4 settings under the adapter settings, still no dice.   I have tried with a straight and cross cable.  

Any thoughts?

And yes. I have no idea what I am doing %80 of the time.

TIA 

[Electronics Wizardy]

You want a swaitch here. And for this use, don't use the wan port of the AE>

[Nbd508]

2 hours ago, Electronics Wizardy said:

You want a swaitch here. And for this use, don't use the wan port of the AE>

I'm sorry, I don't follow?

Also I should mention I gain access AE to Macbook wired to the WAN, but not PC to WAN

[Electronics Wizardy]

7 hours ago, Nbd508 said:

I'm sorry, I don't follow?

Also I should mention I gain access AE to Macbook wired to the WAN, but not PC to WAN

for this use don't use the wan port at all. You want a switch. Get this. https://www.amazon.com/gp/product/B00QR6XFHQ/ref=s9_acsd_top_hd_bw_b1BCw_c_x_3_w?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=merchandised-search-3&pf_rd_r=QKCFKSFA22G6A2JNSH17&pf_rd_t=101&pf_rd_p=fbe1eefb-ab6b-504c-a54d-20a2a64b7989&pf_rd_i=281414