Run netstat -aon | findstr :443 one more time. Now you should see the Veeam services (like VeeamBackupSvc ) happily listening on port 443.
Now, find which application owns that PID: Run netstat -aon | findstr :443 one more time
"The required port 443 is already occupied by another application." Run netstat -aon | findstr :443 one more time