My laptop is always connected to my office LAN (using DHCP) via the onboard Ethernet adapter (Local Area Connection 1). This is my primary connection that I use for all of my work applications, the Internet, etc.

I've got a standalone server sitting on my desk that I need to FTP into (using a static IP address) from time to time to get some files off of it (it's running a proprietary OS, but it shouldn't matter). Because the standalone server is not on the office LAN (that is not an option), I have been disconnecting my laptop from the office LAN and then connecting it to the standalone server to copy these files off... But when I do that, all of my laptop's applications that are running (obviously) lose their connection to the office LAN, which causes a lot of problems.

To fix this, I added a second Ethernet adapter to my laptop in the form of a PCMCIA card (Local Area Connection 2). That way, I should be able to leave my laptop connected to the office LAN while simultaneously connecting to the standalone server.

Typically, I leave Local Area Connection 2 (LAC2) "disabled" in my "Network Connections" under Win XP until I need it. When I do need it, I'll connect the Ethernet cable from my standalone server to my laptop and I will go in there and "enable" the LAC2 connection.

When I do this, I can communicate with the standalone server just fine, however, all of the applications, etc. on my laptop get disconnected from my office LAN, even though the LAC1 connection is still "enabled". When I run "ipconfig" from the command line, it reports that I am still connected to both networks, and I've got a valid IP address on both, however, I cannot communicate on the office LAN until I disconnect or disable the LAC2 to my standalone server.

Every once in a while, I will configure a new static IP address for my LAC2 (standalone server), but other than that, nothing has changed as far as the two LAN configurations are concerned.

So, my question is, what could be causing this and how can I fix it? Like I said, I'm really confused because after connecting to LAC2, Windows reports that I'm still connected to LAC1, but I cannot access any resources on the office LAN (LAC1) until I disconnect from LAC2. What gives?

Thanks for any and all advice!

Well, I just figured it out...

If I run the "netstat -r" command while I'm only connected to my office LAN, it shows my Default Gateway as being correct for that LAN (it's the one obtained by my office's DHCP server). However, if I enable the second LAN connection to my standalone server and then run "netstat -r", the Default Gateway changes.

So, I went into the configuration for my standalone server's LAN connection and removed the Default Gateway IP address completely. Now, when I enable both connections, I have full access to both my office LAN and to the standalone server.

Huzzah!