Npcap is not included in the CustosXI installer. CustosXI uses SharpPcap, which depends on Npcap for live packet capture on Windows.
When you need it
- Live packet capture and deep traffic inspection
- Start capture on boot (Settings → General) and the capture test in the setup wizard
When you can skip it
Without Npcap, these features still work:
- DNS sinkhole and DNS-level blocking
- Windows Firewall integration and enforcement
- Public blacklist and reputation workflows that do not require raw packets
- Most dashboard and settings UI
Installation
- Download from the official site: npcap.com
- Install with WinPcap API-compatible mode (recommended in CustosXI UI and installer text)
- Restart CustosXI or refresh capture settings; the app shows an in-app banner when Npcap is missing
Install only from official Npcap sources. See Security and Third-party notices.
Custos