Sometime when I schedule a meeting or I send the invitation to a group of employees. The invitation goes the wrong person. Example: last week a person from Verizon sent me an invitation for a meeting; the invitation went to me and also went to someone that was not included in the list of invited

Check for OUtlook rules or delegates or transport rules.

what i should be checking there?

Check for any rule that may be forwarding meeting requests or delegates. Are you sure the other person wasnt BCC:? What does message tracking show?