Most Unix / Linux operating system distributions, as well as Mac OS X, include Tcl/Tk. If not already installed, you can use your system's package manager to install the appropriate packages.
If you don’t already have Tcl/Tk Aqua installed on your computer (most MacOS X installs have it), you will get this error message. To resolve it, simply go to the website for Tcl / Tk Aqua and download the latest version:
If you have an older version of Tcl / Tk Aqua, you’ll benefit from upgrading.