When encountering a warning about antivirus protection malfunctioning, the first step should be to isolate the computer from the network to prevent potential spread of malware. Updating the endpoint protection software is also crucial to ensure the latest virus definitions and security features are in place to effectively identify and remove the threat.

After implementing a change authorized by the change advisory board (CAB), the technician should document the date and time of change as part of the post-implementation review. This helps to track the change history, verify the success of the change, and identify any issues or incidents caused by the change1. Documenting the purpose of the change, the risk level, and the findings of the sandbox test are all part of the pre-implementation activities that should be done before submitting the change request to the CAB2.