NCCD405-1020 e-file error
You get this error when you file a North Carolina-combined return, because the application doesn't currently support e-file for combined returns.
Error message
Type NC Record Name CD405 Form Occurrence No. 0 Field Sequence No. 0 Form No. NCCD405 Form Page No. 1 Reject Code NCCD405-1020 Extended Reject Code 0 Error Message [CD-405] If the taxpayer FEIN is approved as the Principal Member of a combined filing, the Combined Return checkbox must be checked, and CD-405CW must be submitted; otherwise, the Combined Return checkbox must not be checked, and the CD-405CW must not be submitted Error Category Incorrect Data Rule Number NCCD405-1020 Severity Reject NCCD405-1020
Solution
Paper-file the return. North Carolina combined return e-file isn't currently supported in the application.