How do I know whether I have any errors in my T2 or T1 Tax Return?

The Review Diagnostics function will display all errors or issues in your T1 or T2 returns prior to submission. You must resolve all errors (marked in Red) otherwise the system will not allow you to file. To resolve the issue, click on the error and the software will direct you to the schedule where the error was detected. Cautions in yellow will not prevent you from filing but they may point out issues which may cause complications after filing (for example incorrect amounts or entitlements which can trigger an audit by the CRA). Information items as the name implies are meant to be informative and will not affect the return in any way.