42 Computer security consultancy in the field of scanning and penetration testing of computers and networks to assess information security vulnerability; Computer security consultancy in the field of data protection, data recovery, system protection, and system recovery; Computer security service, namely, hard drive erasure; Computer security service, namely, restricting access to and by computer networks to and of undesired web sites, media and individuals and facilities; Computer security services in the nature of administering digital keys; Computer security services in the nature of providing authentication, issuance, validation and revocation of digital certificates; Computer security services, namely, restricting unauthorized access to hard drives, computer network, and websites; Computer security threat analysis for protecting data; Computer security consultancy; Maintenance of computer software; Maintenance of computer software relating to computer security and prevention of computer risks; Updating of computer software relating to computer security and prevention of computer risks; Consulting services in the fields of selection, implementation and use of computer hardware and software systems for others