The following explains what the most common CT600 error messages mean and describes what to do:
“Code : 1607 Box Location : Computations : Information within the computations does not match that on the CT600”
This usually means that the Company Number in the iXBRL Accounts file does not exactly match the 8 digit Company Number in the CT600. To overcome the problem, add leading digits to the Company Number, e.g. 07654321, and then generate the iXBRL Accounts file again.
“Code : 3303 Box Location : Accounts : One of the Inline XBRL documents contains malformed xml. Please check the attachment and resubmit.”
“Code : 1605 Box Location : iXBRL : The attachment with the file name IR Format_1 is in an invalid format.”
One cause of this problem is the inclusion of a line featuring a DOCTYPE declaration, i.e. <..DOCTYPE …… >, near the start of the accounts file. Remove this line by opening the iXBRL Accounts file in a text editor (we recommend TextPad), deleting, and saving the file.
“Code : 3303 Box Location : Computations : One of the Inline XBRL documents contains malformed xml. Please check the attachment and resubmit.”
“Code : 1605 Box Location : iXBRL : The attachment with the file name IR Format_1 is in an invalid format.”
Both of these error messages are due to problems with the format of the iXBRL Computations file, and probably mean that you are not using the latest version of the Ftax CT600, or you are not using the Ftax iXBRL Computations. Transfer your data to the latest version and generate the iXBRL Computations file again. Never Open and then Save iXBRL files as this may add extraneous information.