How would I check if it's because of antivirus software?
Do you have any special antivirus software installed on the PC? Then open that and see, if it has blocked StarbaseSim from opening. It should tell you somewhere, but depends on the software of course.
Else search for "defender" and it should bring you up the windows anti virus stuff where you can find a report of its activities to see if it blocked it. Normally, that one shouldn't block it though.
There might be also other reasons for that message appearing. But I'd have to do some more googling myself first. Main reasons seem to be missing or corrupt files or antivirus blocking it though.