Several code errors can appear while the Netfile process. If you have received an error message you may consider some minor issues related to some small typos such as invalid characters. Please visit Error message: Invalid characters when trying to use NETFILE, here you will find a list of invalid characters that you need to remove in the Netfile process.
If this is not your case, you also can visit this FAQ – Why do I get an error when I try to submit my return through the CRA’s NETFILE service? to see other common code errors and how to try to fix them.
You also may be interested to see other options to Amend your tax return. Please visit this FAQ- How can I Amend my tax Return?
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