Why can't I use my Intuit Online Payroll UserID and password?
It's all about security. Your payroll contains extremely sensitive information about you, your business, and your employees. The keys to seeing this information are your Intuit Online Payroll User ID and password: share them only with people who are working on your payroll.
Your Time Clock doesn't contain sensitive information: it merely lets your employees tell you when they're arriving to work and leaving. Having a separate ID and passcode for your Time Clock protects your payroll.
For example, the Time Clock might accidentally get turned off. If you're away from the Time Clock computer, you can give someone the Time Clock ID and passcode without having to worry about them seeing any details from your payroll.