Most payroll questions an employer asks fall into three groups: what must be done and by when, how an unusual case is treated, and who is responsible when something goes wrong. The first group has fixed answers, the second depends on written method, and the third depends on a contract.
Questions with fixed answers
When registration must happen, when filings and payments are due, how long records must be kept, and what must appear on a payslip. These are set by rules rather than by preference and a vendor's default is not authority. Look them up once for your jurisdiction, write them in a calendar, and stop guessing at them.
Questions that depend on your method
How a part period is calculated for a starter or leaver, how an annualised term time salary is worked out, how holiday pay is derived for variable hours. Several defensible methods exist for each, and what matters is that you use one consistently, document it, and apply it to everybody. Inconsistency is what turns these into disputes.
Questions that depend on your contract
Who pays a penalty caused by a provider error, what a bureau covers, how quickly a correction can be made. These are answered by the agreement rather than by the software, and the time to establish them is before signing rather than during the incident.
Questions people ask about payroll questions
Where should an employer look for authoritative answers?
The tax authority and employment guidance for your jurisdiction. Vendor help pages are useful and are not the source.
Who is responsible if a bureau makes an error?
Generally the employer to the authority, with the contract deciding what the provider covers. Read the clause.
How do we handle a question with no clear answer?
Choose a defensible method, document why, apply it consistently, and take advice where the amounts are material.