Assuming that you are using Outlook as your email client app. you can export the *.pst file from the NT machine to a shared location on the network. Then import the *.pst file into Outlook on the Windows 2000 machine. Steps:
1. On the NT machine, log in as the user and open Outlook. Make sure in the folder list box that the Personal Folders icon is highlighted.
2. Select File, Import and Export, select Export to a file, click Next, scroll down and select Personal Folder File (.pst), click Next, highlight Personal Folders in the Export Personal Folders dialog box, select include subfolders and then click next, this is where you can rename the file %filename.pst% and browse to the network share location to save the file. If the pst file is large it may take a few minutes to copy out, especially over a network connection. Click Finish.
3. On the Windows 2000 machine, log in as the user and open Outlook.
4. Select File, Import and Export, then select Import from another program or file, click next, then scroll down to highlight Personal Folder File (.pst), then click next, then browse to the network share location of the pst file you just created, click next, select the location in Outlook for the file and select finish.
That's it in a nutshell.
Good luck!
ET