In the User Identification section, enter the UserID and Password.
Click the 'Download NTv2 File(s)' button.
Select Canada to see the list of available downloads.
Select the check box for NTV2_0.gsb and then click the Submit button to begin the download. In addition to the NTv2 download, there is an online application available for NTv2 transformations on the Natural Resources Canada website: NTv2 Tool