Scan if Ping Fails
In Internet Scanner, this option tries to connect to the host if ping fails. In a typical scenario, a scanned network may block the ICMP (ping) packets, appearing as if there is nothing out there to answer. When
Scan if Ping Fails is in effect, Internet Scanner attempts to scan even when the
ping test fails.
This scanning method is thorough but also more time-consuming. If the network
that is being scanned is not blocking ICMP packets, turning this option on
unnecessarily increases the time it takes to scan a network. To test if an ICMP
packet is allowed through the network, try to ping a host that is known to be
online. If ping reports that the host is alive, turn off the Scan if Ping Fails
option to save time.