Unable to set CORS headers for 404 & 403 error codes

[Teja]

Hi Team,

We have a requirement to put the cors headers at everytime even in error state as well and it is working fine whenever there is an 400, 401, 409, 500.. for all these errors but it is not working properly for 403 & 404 error codes.
And Im getting error like below

 No 'Access-Control-Allow-Origin' header is present on the requested resource.

 May I know why cors headers are not adding for 403 & 404 status codes.

Here Im using AssignMessage Policy to set up cors haeders

Thanks In Advance.