abc self assessment


I have already submitted my return via another route. Can I use ABC SA100 to submit an amendment?

ABC SA100 2014 can be only be used to submit amends to a return where it was used for the original submission- however in ABC SA100 2015 it is possible to submit amends to returns that have been made by another route.

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Is the 'tax owed' figure at the top tax I owe HMRC or they owe me?

If the number at the top is positive, it is tax you owe to the HMRC; if negative you have overpaid tax and HMRC owe you.

If you click on the Summary button next to that, you'll see a breakdown of how that is reached, in a .pdf.

After you add Payments On Account information, and after you submit, you'll see the amount you owe by 31 Jan, which can be different to the tax owed for 2013-14 since that incorporates POA from last year and POA for next year.

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I am having trouble viewing the tax summary, or help files - why?

Our product uses the free Adobe Acrobat Reader to display the tax summary and, on Windows, the HMRC help documents.

Please ensure you have that installed, and if not, install it from

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Why do I get "Authentication Failure. The supplied user credentials failed validation for the requested service."?

That message means that the HMRC User ID and HMRC Password you entered when submitting were rejected by the HMRC.

The user ID and password you enter need to be the same user ID and password you would use to log in to the HMRC Self Assessment website: i.e the username and password the HMRC gave to you - and those details will be associated with a specific UTR (Unique Tax Reference), which must be the UTR you enter in the 'About you' section at the start of the form.

Suggested steps:

  1. Check that you are doing a return for an Individual not a Partnership (SA100 is for an individual, though that individual may contain income received from one or more partnerships). For returns for a Partnership itself, the SA800 should be used (which we do not offer a product for 2013-14)
  2. Use the 'Show' button in the 'Submit' popup to look at the password you have entered
  3. Remember that the password is case sensitive - and you must make sure you do not have any extra spaces before or after it.
  4. Check that UTR number you have entered in 'About you' is correct
  5. Go to and enter the gateway ID and password you are using to check that you can log in - that will check that you are registered for the online Self Assessment service and that the username and password is correct
Once logged in, click 'Next' to get to the main screen and look for your UTR: in the main version of the HMRC website it appears in the top right (see attached image) but you may see a different version if they are trialling a different interface. Back to top

TypeError: Error #1009: ... PopUpManagerImpl/handleAccessibilityForNestedPopups()

If you get an error that starts 'TypeError: Error #1009' then has 'handleAccessibilityForNestedPopups()' or 'addModalPopUpAccessibility()' in the next line, please visit to download and install the latest version of SA100 2014, which includes a fix for that issue. Back to top

With screen reader on I get an error when I submit - what can I do?

If you get an error starting "TypeError: Error #1009" when you submit, please

1. Kill the application using task manager

2. Turn off the screen reader (e.g. Windows-enter)

3. Relaunch the application and submit

This is an issue with screen reader on specific version of windows; we will work to provide a fix from our end as soon as possible.


Example error trace:

TypeError: Error #1009: Cannot access a property or method of a null object reference.

        at mx.managers::PopUpManagerImpl/addModalPopUpAccessibility()
        at mx.managers::PopUpManagerImpl/modalPopUpCreationCompleteHandler()
        at mx.core::UIComponent/dispatchEvent()


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I've purchased a key, but have closed the 'Evaluation mode' popup - how do I get it back so I can paste my key in?

If you exit the app and restart that popup will appear again, or you can reopen it by clicking the 'Summary' button at the top of the app, or the 'Export' button in the bottom left (or the 'Submit to HMRC' button if you are at that stage). Back to top

I purchased a license for ABC SA100 but reinstalled my operating system (or changed to another computer) - can I use the activation key on the new computer/OS installation?

Yes, you can re-enter the activation code you were sent to activate the application on a different computer.

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Why can't I submit the form to HMRC when it still has validation errors?

The HMRC systems will reject submissions that do not pass validation tests - for example not having mandatory fields populated, or values that appear to contradict each other. Therefore the ABC application will insist that all errors have been fixed before submission.  However, since the ABC application performs all the calculations that HMRC will do, you are able to view the total tax you owe based on the data you have entered at any point, even if you have validation errors outstanding.

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Why does the submission process to the HMRC take so long?

The HMRC servers are designed to handle a large number of simultaneous submissions, and to always either succeed in processing or give a clear message and allow submission to be continued later. In order to make that possible, the servers process your submission via several different steps. There will always be a delay between each step, and at very busy periods (for example the last week of January) HMRC servers can take a significant amount of time to handle the queue. The ABC application will keep you informed of progress, and if the submission does fail to be processed, you will get a clear message and be able to try again.

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What happens if my network connection goes down during the submission process - how will I know if the HMRC got it?

Whatever happens during submission, you will get a clear message regarding your status. For example, if your computer runs out of power during a submission, when you restart the application you will see a message stating whether the submission succeeded or failed, and you can continue the submission process where you left off.

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How do I save what I have entered so I can add more later?

Your data is automatically saved as you enter it - there is no need to press a 'Save' button. You can exit the application at any time, and when you launch again your data will be in place and you will automatically reopen the page you were on when you exited.

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For my return I need to attach supporting information, how do I send that with my return?

You can attach .pdf files to your return, up to a maximum of 5MB for all attachments.

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I've submitted to the HMRC but have realised I made a mistake, what can I do?

You can make the changes you need and resubmit. ABC SA100 supports submitting amended returns, so the only limit is a maximum number of submissions within a tax year enforced by the HMRC (at time of writing they allow amendents to be submitted up to 9 times).

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Two of us need to do our tax returns on the same computer - can we do that and do we need to buy two activation codes?

Yes, each individual doing a return will need an activation key.

For 2014-15 returns, multiple users can submit returns from the same ABC installation

For 2013-14, multiple users can do their returns on the same computer, but ABC should be installed on a different user account for each return. 

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What can I do with an unactivated version of the application?

Unactivated, the ABC application is fully functional except you cannot submit to the HMRC.

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What tax scenarios are not supported?

ABC SA100 does not contain the supplementary forms for:
  • Lloyd's Underwriters (SA103L)
  • Foreign (SA106)
In addition the following scenarios are not supported:
  • Multiple chargeable event gains
  • Disclosures regarding the Swiss/UK Tax Cooperation Agreement
The following scenarios can be submitted, though may require additional calculations to be performed manually and detailed via an attachment:
  • Capital Gains Tax
  • Cases involving Top Slicing Relief
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What are the system requirements for ABC SA100?

ABC SA100 can be installed on a PC running Windows 7 or above or on a Mac running OS X.

On Windows, Adobe Reader 7.0 or above is required, to view the HMRC notes .pdf files and the Tax Calculation Summary.

On Mac, Adobe Reader is required to view the Tax Calculation Summary.

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Where is my data stored?

Your data is stored entirely on your local computer until the point you submit to the HMRC, where the form content you have chosen to submit is sent over secure HTTPS directly to the HMRC.

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Can I change my details after I submit to the HMRC?

Yes. The HMRC allow submitting an amended return, and our form app doesn't limit how many times you submit amended returns.

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