Final answer:
It is not recommended to use E-Verify to confirm the eligibility of employment for all existing employees.
Step-by-step explanation:
When a company begins using E-Verify, it is not recommended to retroactively confirm the eligibility of employment for all existing employees. E-Verify is typically used for new hires to verify their work eligibility. Existing employees who were hired prior to the implementation of E-Verify would have already provided the necessary documentation to prove their work eligibility through the normal hiring process. Additionally, retroactively verifying existing employees using E-Verify could potentially violate employment laws and result in discrimination.