Mac/Windows sharing problems

I am having some trouble getting Mac/Windows sharing to work correctly. I used the guide on MacRumors Guides to get everything set up and running, and I was able to connect successfully to my Windows machine. The only problem was that I couldn't use the Internet. I changed some settings and managed to get the Internet working, but now I can't connect to my Windows machine.

Here's the relevant part of my network setup:

-Windows machine-
Wireless access: none
Ethernet: directly connected to Mac machine
Internet access: none

-Mac machine-
Wireless access: AirPort
Ethernet: directly connected to Windows machine
Internet Access: via AirPort

Relevant Network settings on the Windows machine:

Configuration method: manual (I gave the machine a static IP address to make connecting to it simpler)

Relevant network settings on the Mac for AirPort:

Configuration method: DHCP
AppleTalk: off

Relevant network settings on the Mac for Ethernet:

Configuration method: DHCP (uses a private address since no DHCP server is available on that connection)
AppleTalk: off

Network Port Connection Order:

AirPort, Ethernet, FireWire, Bluetooth

Note: If I change the order to Ethernet, AirPort, FireWire, Bluetooth, I can connect to my Windows machine but not use the Internet. If I use the order listed I can use the Internet but not connect to my Windows machine.

 

That's the goofy thing. If I enable Windows Sharing on the Mac and connect to the Mac from the Windows box it works perfectly (I've used the network drive approach in the past with success). Connecting to the Windows box from the Mac fails.

 

I tried that. It works with Ethernet first but not with AirPort first. It baffles me since I thought Mac OS X was multihoming and could deal with multiple connections at once.

 

As it turns out, I was wrong about the DHCP thing, I changed my Mac's Ethernet card to a static IP address on the same subnet.
Windows:

Windows IP Configuration

Host Name: ASHLEY
Primary DNS Suffix: (blank)
Node Type: Unknown
IP Routing Enabled: No
WINE Proxy Enabled: No

Ethernet Adapter Local Area Connection:

Connection-specific DNS Suffix: (blank)
Description: Intel(R) PRO/100 VE Network Connection
Physical Address: 00-11-11-03-36-CF
Dhcp Enabled: No
IP Address: 192.168.1.201
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.1.200
DNS Servers: 192.168.1.200

Mac:

lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
inet 127.0.0.1 netmask 0xff000000
inet6 ::1 prefixlen 128
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1
gif0: flags=8010<POINTOPOINT,MULTICAST> mtu 1280
stf0: flags=0<> mtu 1280
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
inet6 fe80::214:51ff:fe2f:c9f4%en0 prefixlen 64 scopeid 0x4
inet 192.168.1.202 netmask 0xffffff00 broadcast 192.168.1.255
ether 00:14:51:2f:c9:f4
media: autoselect (100baseTX <full-duplex>) status: active
supported media: none autoselect 10baseT/UTP <half-duplex> 10baseT/UTP <full-duplex> 10baseT/UTP <full-duplex,hw-loopback> 100baseTX <half-duplex> 100baseTX <full-duplex> 100baseTX <full-duplex,hw-loopback> 1000baseT <full-duplex> 1000baseT <full-duplex,hw-loopback> 1000baseT <full-duplex,flow-control> 1000baseT <full-duplex,flow-control,hw-loopback>
en1: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
inet6 fe80::214:51ff:fe81:ee01%en1 prefixlen 64 scopeid 0x5
inet 192.168.1.103 netmask 0xffffff00 broadcast 192.168.1.255
ether 00:14:51:81:ee:01
media: autoselect status: active
supported media: autoselect
fw0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 4078
lladdr 00:14:51:ff:fe:2f:c9:f4
media: autoselect <full-duplex> status: inactive
supported media: autoselect <full-duplex>

 

Success!

After fiddling with the settings some more I got it to work properly. I can now connect to my Windows box from my Mac, connect to my Mac from my Windows box, and use the Internet on my Mac.

As it turns out, I have to use DHCP for assigning Ethernet addresses for both the Mac and the Windows box, otherwise the Mac gets confused because it thinks it should be able to connect to the Internet via Ethernet (when it has a static IP address) but can't, and refuses to try AirPort to connect to the Internet. Once I figured that out, and put Ethernet first in the port order it worked!