Hi. We have a license for NetScan and use v8.1.6 64 bit portable.
I configured a scan for a 172.16.60.0/22 network. Only 1024 hosts. Even though I see a long list of devices for which the scan has finished successfully, it keeps scanning for ever and showing "Scanning..." in the bottom left corner of the application window.
It sounds like the scanning of some of your devices has not completed. You can scroll the list in the main window up and down to find those devices: they would have a 'question mark' icon rather than the 'computer screen' icon.
Depending on your scan settings, scanning certain devices may take a long time. For example, if you are doing a port scan and a device is firewalled, it will take a considerable amount of time for this scan to complete. Likewise, slow-responding devices such as mobile phones and tablets may take a long time to be scanned.
Check which devices are still being scanned and ponder what is common between them. Turning off some additional scans options may resolve this issue or suggest which type of scan does not complete.