Do you have AutoCAD installed on your computer? If so, .scr extensions are AutoCAD script extensions and DDS will not run properly unless that is fixed. When attempts to run the tool are made it opens in Notepad with non-readable characters as you describe.
If that's the case, please download the corresponding file for your operating system:
Extract (unzip) the file onto your desktop, double-click on it and choose Yes
to merge the file into the registry when prompted. Afterwards you should then be able to run DDS.scr.
Edited by quietman7, 14 December 2011 - 06:14 PM.