If an engineer receives a 403: Forbidden error when attempting to download a packet capture file from Cisco Secure Firewall Management Center (FMC), the issue is likely due to HTTPS not being enabled in the device platform policy. To resolve this issue, the engineer must enable HTTPS in the platform policy. Steps: * In FMC, navigate to Policies > Device Management > Platform Settings. * Edit the relevant platform policy. * Enable HTTPS for the device. * Deploy the changes to the FTD device. This ensures that the FMC and FTD device can securely transfer the packet capture file over HTTPS, resolving the 403 error. References: Cisco Secure Firewall Management Center Administrator Guide, Chapter on Platform Settings and HTTPS Configuration.