A new computer is likely running Windows Vista. Outlook 2000 is not
compatible with Vista. It *may* work if you install it in Corporate/Workgroup
mode, but you're likely to run into other issues.
On top of that, if it's an OEM version of Outlook (i.e., one that came
preinstalled on the original PC), then it is not legal to install it on
another PC. The license is tied to the original hardware.