Current version Installs, but won't open

I have tried several downloads of this program. It installed on Windows 7 and 10 easily, but the program will not open.
It goes through the motions of opening - the icon spinning - then nothing.
Nothing shows in Task Manager. No problem with other programs - MYOB (which I’m trying to replace) opens. Office, etc… no issue. Just this.

I have done full removal, restart (not reboot) to no avail.
This occurs on existing and formatted machines.

i5, 8Gb, 1200Gb free.

Did you install under the default location or did you select another:

Default = C:/users/(user name)/appdata/roaming/ Manager

What Application Path is shown under About Manager

It should match = C:/users/(user name)/appdata/local/Manager

If yes, what files are located there?

Default install.

1 file in the folder: 00000000000000000000000000000000.manager