Where can I update Massachusetts Schedule C. Main Business, Principal Business Activity Code (PBC), and Business Address? The return keeps getting rejected without them

All of the base information for the Schedule C is posted to your federal tax information.

Go back to the Federal Tab

1. Select Income & Expenses
2. Choose Self-employment income and expenses.
3. Click [Review] on your business
4. The screen will show Here's your work info.
5. Click [Edit] next to General Info.
6. Post your needed changes.