Final answer:
To secure a device from unauthorized access and malware, it's advised to use a combination of system file checks, file encryption, login requirements, and a host-based firewall.
Step-by-step explanation:
To protect a device from unwanted access and malware that may have gotten past its firewall, there are several effective strategies. Running the system file checker tool on the device can help repair corrupted system files and restore system integrity. Utilizing file encryption can protect sensitive data by making it unreadable to unauthorized users. Requiring users to log in to access the device adds a layer of security by ensuring that only authorized personnel have access. Moreover, the use of a host-based firewall offers an additional line of defense by monitoring and controlling inbound and outbound traffic directly on the device itself.