Paycheque access denied


I am currently working on an assignment for school. For some reason the "Paycheque" tab is denied. Specifically "Create Paycheque" and "Adjust Paycheque" are light grey and can not be accessed. I can "Look up Cheque". I have access to the "Payroll Cheque Run", but when I enter someones payroll information, the CPP and Income Tax are different than my teachers entries. Is there a setting I am missing. I have not altered the files that my teacher sent, so I am lost on what I can do. Any help would be greatly appreciate!