If a pre-14.10 version of TTU is installed then please use the uninstall vb script to uninstall before installing 17.00. See Uninstall Teradata Tools and Utilities Pre-14.10 for details.
Any pre-15.10.10 version of TTU must be uninstalled before installing 17.00. See Uninstalling Teradata Tools and Utilities 14.10 and Later for details.
If a 15.10.10 or later release is installed on the system, then 17.00 can also be installed on the same system without uninstalling the 15.10.10 or later release. See Multi-Version Support for details.