Network containment isolates a host from normal network communication to prevent lateral movement and attacker-controlled access. By default, a contained host cannot reach patching infrastructure, so operating system patch jobs fail unless specific exceptions are added. The Falcon configuration point for this is the Containment Policy , where administrators allowlist specific IP addresses that contained hosts may continue to communicate with. The official guidance states that to install patches on network-contained hosts, administrators must add the IP address of the Windows Update source or patching source to the environment’s containment policy. FQDN allowlisting is not the correct answer in this context; the supported containment exception is IP-based. Removing containment would restore connectivity but would also eliminate the protective isolation during a zero-day remediation scenario. Firewall Policy is not the control that governs Falcon network containment exceptions. Reference topics: Network Containment, Containment Policy, Patch Windows Hosts, Policy Application.