Depending on how comfortable you are you can go to the config files and back them up and then rename or delete them…Now try starting DT it should make new empty config files and run. If so then your configuration must be corrupt in some way…You can also run DT by installing it in a non-standard directory…make one up…ie not the one offered by the install. Now when you run DT use a command line slash --configdir “path” Create a blank directory and where I listed path enter the text there… This should run DT without any connection to your previous or installed versions…THis can help to identify what might be wrong…
In fact you can even use this second approach for your installed version…just Make a new desktop shortcut by copying your current one then and then add my instructions above to the command line in the shortcut by going into properties and making the edit… This will run your current install but use a new blank config files folder… if the issue still persists then there may be other issues but this is a good starting point…