Inconclusive / Scan Interference reports indicate either that a firewall, IDS, or IPS is blocking the scanner from connecting to your servers or you're scanning a router or device that does not host any services. In case of the former, you and or your host and or your ISP will have to whitelist our IP range for incoming connections.
The IP ranges we use:
CIDR: 126.96.36.199/28 which translates to: 188.8.131.52 through 184.108.40.206
CIDR: 220.127.116.11/28 which translates to 18.104.22.168 through 22.214.171.124
CIDR: 126.96.36.199/27 which translates to 188.8.131.52 through 184.108.40.206
If the target which you're scanning does not host any services but is on a subnet with others that store or process credit card data, these can be marked as 'dead host exceptions' and will be compliant. There are links at the bottom of the vulnerability reports to report them as a False Positive.