How do I install the Classic PCI or the Digi Neo using the 40002448 driver in Windows 2000?

You need administrative privileges to update device drivers. Please be sure you are logged into Windows as Administrator or as a user that is a member of the Administrators group. 
To update an existing Neo and ClassicBoard PCI driver, first unzip the driver installation package to a folder of your choice. 
Next, locate and follow the instructions for your specific operating system. Note that the Update Driver functionality available via the Device Manager is not supported for this product, so please follow the instructions carefully.

WINDOWS 2000: 
a. First, uninstall the previously installed device driver. Run the Add/Remove Hardware Wizard from the Control Panel: Start > Settings > Control Panel > Add/Remove Hardware Click "Next >" Select "Uninstall/Unplug a device" Click "Next >" Select "Uninstall a device" Click "Next >" Find and select the adapter from the list Click "Next >" Select "Yes, I want to uninstall this device" Click "Next >" Wait for confirmation and click "Finish" Be sure to uninstall each adapter that needs to be upgraded. Alternatively, one may uninstall the adapter using the Device Manager. Expand the category, "Multi-port Serial Adapters" and find the adapter to uninstall. Next, right-click on the adapter and select "Uninstall...". Follow the prompts to complete the uninstallation. Go to the directory with the new drivers. Run the dgcbcln.cmd program to remove Digi''''s oem driver files.
b. Tell Windows to scan for new hardware. Again, find the Add/Remove Hardware Wizard located in the Control Panel directory of the Start Menu. Click "Next >" Select "Add/Troubleshoot a device" Click "Next >" Wait while Windows searches for new hardware. Windows will display the "Found New Hardware Wizard" Alternatively, one may reboot Windows to conjure the "Found New Hardware Wizard". 
c. Follow the instructions for the "Found New Hardware Wizard". From the "Locate Driver Files" screen, be sure to select "Specify a location" to point the wizard to the location where you unzipped the driver installation package. 
d. Follow any other instructions to complete the installation. 
e. The "Found New Hardware Wizard" may reappear a number of times depending on the number and type of adapters you are installing.