HMRC Error 3320 or Error 3321 CT600 Submission Computations or Accounts

HMRC Error 3320 or Error 3321 - submission of CT600 with Computations or Accounts


When submitting CT600 return with a set of accounts and computations in iXBRL format, HMRC servers may reject the submission with a HMRC validation message:
  • Error Number: 3320
  • Error Location: Computations
  • Error Type: business
  • Error Text: The period to which this Return's Computation applies does not coincide with the effective from/to dates of the referenced Computations Taxonomy. Please correct and re-submit.
  • HMRC server may display:
  • Error Number: 3321
  • Error Location: Accounts
  • Error Text: The period to which this Return's Accounts applies does not coincide with the effective from/to dates of the referenced Accounts Taxonomy. Please correct and re-submit.


HMRC updated their servers with RIM Artefacts and Taxonomy changes which were deployed into the Live service on 11 December 2017.

Along with these RIM Artefacts and Taxonomy changes, HMRC also removed some DPL taxonomy that was used for computations for earlier periods. In effect from 11 December 2017, HMRC have stopped accepting the 2013 DPL for Accounting Periods starting after 31/12/2015 and there is no backward compatibility. Any submissions made for APs starting after 31/12/2015 using older version taxonomy will be rejected by HMRC.


There are three possible solutions:
  1. Where you have attached Accounts and Computations iXBRL files generated through a third party Final Accounts Production software, please contact your software provider to update or upgrade their software.

    Once you have upgraded your Final Accounts Production software, generate the iXBRL documents again, and attach the newly generated iXBRL files into Andica CT600 software.

    If your Accounts and Computations were tagged by a tagging service provider, you will need to get them to tag these correctly.

  2. Where you are using the free basic inbuilt Accounts and Computations template within the CT600 software Version 2017, follow this advice:

    Important: This option should only be used by customers who are on CT600 Version 2017 software for Accounting Periods up to 31 March 2018, Single computer licence.
    Version number displayed on software login screen should be:
    Version 2017.0.0.0
    Version 2017.0.0.1
    Version 2017.0.0.2

    Version 2017.0.0.3

    Customers using Network version of CT600 Version 2017 should contact us by email.

    Warning: Customers using older versions 2016 or earlier should NOT apply this patch, you will break that software and there is nothing we can do about it.

    Customers with Andica CT600 versions listed above should click this link to download and apply a patch to Andica CT600 Version 2017.

  3. Customers using older software - Andica CT600 software Version 2016 or earlier should either:

    1. Purchase a new CT600 version 2017 software from the web shop.

      Thereafter download and install the new version 2017. Refer to the FAQ for software version upgrade.

    2. Attach valid iXBRL Accounts and Computation files with correct Taxomony.

How to install an update:

When you click on the download links, your computer's internet browser takes over the rest of download functions, we do not control that. Your computer's browser will guide you through the download process.
  1. Close the software before installing the update.

  2. To download the update, click on the download link provided above.

  3. If prompted, click Run or Save. Preferably 'Save' the file in a convenient location. It is most likely that your computer's browser will automatically save this file into a Downloads folder.

  4. If you have saved the file, double click on the downloaded file to start installation. If you have chosen to 'Run' installation will start.

  5. Follow the prompts given by the installer. Your system may require you to permit installation.

  6. Important: Check location shown in 'Unzip to folder'.

    Extract the updates into the location where the Andica CorpTax software is installed. If you have installed the software in a different location, change the path shown in 'Unzip to folder' or 'Browse' to the location where you have installed the software.

    Refer to 'Software updates installation location' below for further details.

  7. Click 'Unzip'.

  8. Once the updates have been extracted, 'Close' the extractor. You can now start the software and use it to process your returns.

Software updates installation location:

The default software installation location for CT600 software would normally be:
For computers with 64-bit Windows OS - "C:\Program Files (x86)\Andica\Andica CorpTax"

For computers with 32-bit Windows OS - "C:\Program Files\Andica\Andica CorpTax"

To find out where the software is installed on your computer:
  1. Right click on the software startup icon on your desktop (Ensure you are clicking on the correct software icon)
  2. Select 'Properties'
  3. View 'Shortcut' tab
  4. The path is displayed in either 'Target' or 'Start in' fields.

Check for that location through Windows Explorer. Ensure you extract updates into that location.

Disclaimer: Apart from the information already provided above we cannot advice on how to install the software and updates on your computer. We also cannot advise on how you should configure your computer or resolve your computer system issues. Information provided here is given without any obligations and we will not accept any claims or liabilities for any damages as a result of you relying on the information given here, if in doubt you must consult a qualified Windows system engineer.

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