Please re-download the installer from our website: https://www.gpsoft.com.au/DScripts/download.asp
After downloading it, check that the digital signature is correct and the file is undamaged: How to check for a corrupted installer or main program
Then run the installer, over the top of your existing install. (There's no need to uninstall first, and doing so would wipe your config, so don't do that.)
Once that is finished, please reboot and see if the problem still happens.