Just open a cmd windows by typing cmd into command line window.
Then drag & drop your exe file into your new cmd line windows and press enter.
Copy and paste the output then here into this thread.
Hope this helps.
PS: Did you already restart your machine? If not, it could not be bad and avoid there are are processes left that are disturbing u.
Ensure that u took this file https://files.dynatrace.com/downloads/OnPrem/dynaTrace/7.2/22.214.171.1247/dynatrace-client-126.96.36.1997-windows-x86-64.zip
If it is on windows, check on task manager if there aren't multiple instances od Dynatrace Client process operating. If they are hanging, try to kill them and open once again. You need 64bit windows to run client.