Remote desktop Wifi vs ethernet

I have these two computers, both joined to my home wireless network. I frequently access either of them using RDC from the other with no problem. I have large video files to transfer via the RDC and the wireless network transfer when using Wi-Fi is very slow.

I connected the two computers together via their Ethernet portsone directly plugged into the otherwith a Cat 5 crossover Ethernet cable. With this connection they can both successfully ping each other and access shared folders between the via Windows Explorer when one or both is disconnected from the wireless network.

However, regardless of this disconnected wireless network status, RDC will not connect.

It displays the common message:

Remote Desktop cant connect to the remote computer for one of these reasons:

1) Remote access to the server is not enabled

2) The remote computer is turned off

3) The remote computer is not available on the network

Make sure the remote computer is turned on and connected to the network, and that remote access is enabled.

I first fixed their LAN IP addresses and assigned 169.254.128.110 to one and and .112 last octet to the other, and made both use 255.255.0.0 for the subnet mask.

After that I tried connecting from one to the other on both computers with both computer names and IP addresses. I also tried disabling wireless adapter on both of them, but I cannot determine a configuration at this level that allows the connection from either of the computers.

This is something that I usually do when I want to connect to my laptop, I connect the laptop to one of these with the cable, then disable network adapter on the laptop, that it can be reachable just from cable and run RDC on the PC and done! But I don't know what is wrong between PCs.

What else should I check to find the problem or what else should I further troubleshoot?

My Configuration

I have what we'll name PC1, PC2 and Laptop1 in a home network. They all happily connect each other via RDC when they can reach each other through WLAN.

When I disconnect them from wireless network and wire two of them up at a time using same crossover wire, Laptop1 connects both PC1 and PC2 and vice versa. But PC1 and PC2 wont connect each other, however, they can ping each other.

There is no firewall appliance, no router, no gateway, same subnet mask and assigned static IPs from same range but different from wireless network IP range. PC1 and PC2 are running Win 7 x86 and the laptop is running Win 8.1 x64.