CPP Retroactive payment included in current year T4A(P) - How to deduct?

That doesn't make sense (the help desk response).  A CPP retroactive payment is not deducted in the current year.  It is included in taxable income, but qualifies for a special tax calculation.  CRA calculates the tax on the income as if it had been included in the prior year(s) and credits the current year's taxes if they would have been less.  This is something that is done automatically by the CRA and cannot be "claimed" by the taxpayer.  There is a Form T1198 in Profile which I have never used but appears to be a form where you can report the amount of the retroactive payment, but supposedly CRA already knows that amount.  The Form T2203 you mention is for if there are multiple jurisdictions and other questions in this community indicate that there are some issues with that form.  Maybe you could just override the amount on the Form T2203 (top line) so that it agrees with the income on line 23600 of the T1?

This is what efile help desk suggested might be the problem for the efile reject for T2203 income not equaling net income even though per Profile net income on T1 and T2203 are the same.  Neither efile help desk or Profile support could find reason for rejection.  The CRA error message is (situation 4 is the only one that can apply):

CRA EFILE#90315            One of the following situations applies to your client’s return: 1. You have indicated that this is a multiple jurisdictions (MJ) return but there is no entry on lines 52100 to 52230 on the Form T2203. 2. There is at least one entry on lines 52100 to 52230 on the Form T2203 but you have not indicated that the taxing province is MJ. 3. The province of residence is Quebec and the taxing province is MJ but there is an entry on line 52220 for income allocated to Other (outside Canada). 4. The taxing province is MJ but the total of lines 52100 to 52230 is greater than or less than the net income amount calculated by the Canada Revenue Agency.

Can you tell me - is this a Manitoba tax return, is there business income earned in a province other than Manitoba (selected on the Info screen), and are there any #'s showing on the T2203 Column 4 (fields 52100 to 52230)?  Which I could look at the file - I am usually a pretty good troubleshooter, but it is tough when I do not have the file in front of me.

This is a BC return with entries in every one of box 52100 to 52220 except for PEI, YT, NT, NU and Outside Canada.  After 3 calls to Efile Help Desk over 4 days and 3 calls to Profile Support over the same period I paper filed to get on with other work.  Efile Help Desk's comment about CPP retroactive payment was because the difference in CRA's net income and the T2203 total Column 4 (and Profile's net income) equaled the CPP retroactive payment