Hello Robert
Can you try below approach and see if it helps:
Right-click on any scdoc file and select "Open With" -> "Choose another app". Refer below image.
Next, select the required version (for example SpaceClaim 2020R1), then enable "Always use this app to open .scdoc files" option located at the bottom and then click "Ok". Refer below image.
You are navigating away from the AIS Discovery experience