Using Ref Scheduler Windows Version by itself (without the Web Version) allows the Assigner to use all the functions of Ref Scheduler except displaying the information on the Web.
Ref Scheduler Windows Version requires that the 'Microsoft .Net Framework 4.7.2 Runtime' be installed on your computer.
The Framework may already be on your computer.
The install program will inform you if the Framework needs to be installed.
Install 'Microsoft .Net Framework 4.7.2 Runtime'
here.