I had same the issue - Win 7 Enterprise x64. I was able to run "C:\ProgramData\JP Software\Take Command 20.0\updates\Update\tcmd.exe" directly. However, instead of prompting me to automatically close running programs, I got warning dialog boxes about not being able to replace running files. That happened 2 or 3 times and then the install finished. Everything service was deleted and recreated. It appeared to install correctly anyway.