To install another Ethernet adapter to the ICS host computer, you must log on as a member of the Administrators group.
- Shut down your computer properly, and then physically add the network adapter.
- Restart your computer.
- When the Found New Hardware dialog box is displayed that lists the name of the network adapter that you installed, click Next.
- Click Next on the Install Hardware Device Drivers page.
- On the Locate Driver Files page, click the media option that contains the drivers for the network adapter that you are installing. For example, click CD-ROM drive, Floppy drive or Hard Drive Directory.
- On the Driver Files Search Results page, click Finish.NOTE: When you click Finish, the installation of the network adapter that you just installed is completed.
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Thanks to http://techgurulive.com/2009/03/09/how-to-install-a-second-ethernet-network-adapter-to-the-ics-host-computer/