The Security Password is an added safety feature on Sprout Payroll and ideally, only authorized payroll approvers should have knowledge of the company's Security Password. It is first received via the sign-up email from Sprout Payroll. Please note that this is different from a user's regular password for his or her personal account.
It is used mainly for two things:
1. Approving a payroll
2. Unposting a payroll after being approved
If you've updated your Security Password and forgotten the new one, you can always reset it by following the steps here - How Do I Reset My Security Password? (For Admins).