There is a CRA system issue that is affecting your ability to file. At the moment, there's no workaround solution or expected timeframe to resolve from the CRA for the following error codes: 45555, 45566, 90308 and 95031.
If you see one of these error codes, it's due to a CRA issue affecting all tax software in Canada and on April 14th the CRA announced that they are actively working to resolve these issues.
The CRA is tracking cases affected by these errors, and in the event that an issue is not resolved before the April 30th filing deadline, the CRA has announced that it will provide arrears interest and penalty relief proactively for impacted individuals who file late after having received an incorrect error code that could not be resolved when attempting to file on or before their tax filing deadline.
To be eligible for relief, the CRA requires an impacted customer must have attempted to submit the return electronically on or before April 30th, received the specific error code, and was unsuccessful in resolving the error code despite taking appropriate action.
You can also print and mail the paper file directly to CRA. Here is information on CRA mailing addresses:
https://www.canada.ca/en/revenue-agency/corporate/contact-information/where-mail-your-paper-t1-retur...
We are continuing to provide daily updates here about resolutions and workarounds for other unresolved CRA system errors.
