In the past, Netfile protocols were a little less strict. The CRA's electronic gateway has gotten stricter for 2025. If the software sees an override (a manual change to a calculated field), it thinks the math might be wrong and makes a paper return so that it can be personally checked.
Because your son lives in a basement apartment of your detached house, he technically does live at your address. TurboTax is likely flagging the address because you are entering "Basement" or "Unit B," which makes the software think it’s a separate, independent residence.
Is your son's apartment a legally separate municipal address (e.g., 123-B Main St) or just a suite in your home (123 Main St)?
If it's the same municipal address, the "Live with you" box is the correct way to handle this.
That's why we've been telling you to get in touch with the Product Support team. They can help you fix this because they have tools we don't have here in Community, like screenshare. If the problem still isn't fixed, call them. They're open from 9 a.m. to 12 a.m. EST (Monday through Friday).
