Probably nothing. The overwhelming reason that people seem to get this error is that they have not quite followed HMRC's sign-up procedure.

To sign up to MTD for VAT with HMRC, particularly as an agent, you must go through their sign-up procedure precisely. There are a number of different steps you need to undertake in the correct order and, sometimes, within the correct timescale.

HMRC have published a step by step guide for agents <a href="https://www.gov.uk/guidance/making-tax-digital-for-vat-as-an-agent-step-by-step">which can bee seen here</a> and which they recommend all agents use when signing up to the service.

We have also produced a couple of FAQs on the subject:

<ul>
	<li><a href="https://support.ftax.co.uk/faqs#faq-160-172">one for tax agents</a>, and</li>
	<li><a href="https://support.ftax.co.uk/faqs#faq-160-176">one for non-agents</a>.</li>
</ul>

If you are getting this error, have a look at the above guides - they will almost certainly tell you what you need to do.

In most cases the reason is one of the following:

<ul>
	<li>The agent didn’t use their agent services account (ASA) credentials to link MTD VAT software</li>
	<li>The agent hasn’t signed up to the ASA</li>
	<li>The agent has signed up but has not linked their clients</li>
	<li>The agent has signed up and linked clients but the customer hasn’t subscribed to the Making Tax Digital service.</li>
</ul>

The ‘Ftax Setup Checklist’ video is a step-by-step guide to setting Ftax forms up ready for use. Care has been taken to explain how to overcome every known problem, and so please pay close attention when you watch and re-watch.

<a href="https://www.ftax.co.uk/support/video-guides/ftax-setup-checklist-633">Click here to watch the ‘Ftax Setup Checklist’ video</a>.

Ftax tax returns are pdf forms which run on Adobe Reader. Sometimes the forms can become corrupt, causing them to lose their special properties, e.g. the ability to ‘Save’ form data. If this happens then download a fresh copy of the form from your Ftax Account. Adobe Reader may also become corrupt causing the form to display incorrectly. Reinstalling Adobe Reader via ‘Get Reader’ at <a href="http://www.adobe.com">http://www.adobe.com</a> should overcome this problem, although you will need to go through the Ftax setup again.

Make sure you open the Ftax form into Adobe Reader and not into Preview. This is a common mistake on a Mac.

&nbsp;

The video ‘How to use the Ftax SA100’ takes you through all of the mains steps needed to prepare and submit the SA100 tax return. <a href="/videos#video-119">Click here to watch</a>.

The video ‘How to use the Ftax CT600’ takes you through all of the mains steps needed to prepare the CT600 tax return, along with required iXBRL attachments. <a href="/videos#video-102">Click here to watch</a>. Further help can be found in the ‘iXBRL/CT600’ section of the FAQS.

If you are experiencing problems entering data in the Ftax SA100 or CT600 form, generating a Pdf Copy or iXBRL file, or submitting to HMRC, then you should attach the entire Ftax form with attachments to your Support Request. Cut and paste any error messages you receive into the support request message. This will help the Ftax Support team to respond much faster. <a href="/requests">Click here to send a Support Request</a>.

==&nbsp; You must&nbsp;login using your email address and password ==

== Your email is your username&nbsp; ==

If you have forgotten your password, click 'Forgot Password' on the log-in screen and follow the on screen prompts.

If you have opened an Ftax form and have previously saved your login details on your computer, these may no longer work and the form will show:

<img alt="screenshot" data-entity-type="file" data-entity-uuid="f6c07f76-1d81-491c-9b8e-d65d972d8b16" src="https://static-ftax.s3.eu-west-2.amazonaws.com/cms/inline-images/Untitled-1.png" width="415" height="342" loading="lazy">

If you know your email address registered with your Ftax account, you can simply ignore this (Click OK) and log the form into your Ftax account using your email address and existing password.

You can access the login box at any time from a form by clicking the red question mark on the front page and selecting Ftax Account Login.

If you don't know what email address you have registered with your Ftax account, you can recover your account by accessing the Ftax website at <a href="http://www.ftax.co.uk">www.ftax.co.uk</a> and clicking LOGIN in the top right hand corner. From the login screen select "recover your account" to access the "Forgot Email" box. Follow the instructions and an email reminder will be sent to your registered email address.

If you don't have an email address registered with your Ftax account, or you no longer have access to your registered email account, you can recover your account by accessing the Ftax website at <a href="http://www.ftax.co.uk">www.ftax.co.uk</a> and clicking LOGIN in the top right hand corner. From the login screen select "recover your account" to access the "Forgot Email" box. Follow the instructions to send an email reminder then click 'I did not receive the email' on the website to be re-directed to a 'Reset Unknown Account' form. Complete this form and we will be in touch with you.

If you experience a problem using the automated password/username recovery system (described above) then please send an email to&nbsp;<a href="mailto:support@ftax.co.uk">support@ftax.co.uk</a>&nbsp;&nbsp;which includes the email address used when registering with Ftax, or/and your Ftax Account username. The Ftax Support team can then manually recover your Ftax Account logon details.

If you are experiencing problems when logging into you Ftax Account from an Ftax form, by clicking the '?' in a red ball on the opening page and select the bottom option, then run through the Ftax Setup Checklist either via the FAQ or via the video. If your Ftax Account password contains any character other than alphanumerics or the following characters '@ . ! $ % * ? _ - +', then login to your Ftax Account on the website, go to Account Details, and change the password.

Warning: be careful not to confuse your Ftax Account username and password with you HMRC Gateway User ID and Password.

If you are experiencing problems entering data in the Ftax form, generating a PDF Copy or iXBRL file, or submitting to HMRC, then you should attach the entire Ftax form with attachments to a Support RequestCut and paste any error messages you receive into the support request message.This will help the Ftax Support team to respond much faster. <a href="https://my.ftax.co.uk/support">Click here to send a Support Request</a>.

You are strongly recommended to use the new Ftax Support system. We are confident that you will find it the fastest way to resolve any tax filing problem you are experiencing.

But if you are having a problem using it for the first time, then please email the Ftax Support team directly at <a href="mailto:support@ftax.co.uk">support@ftax.co.uk</a>.&nbsp;

Businesses, self-employed people and landlords will be required:<ul><li>to operate MTD from 6 April 2026 in relation to their trading and property income chargeable to Income Tax and Class 4 National Insurance contributions, if their total qualifying income from these income sources for a tax year exceeds £50,000</li><li>to operate MTD from 6 April 2027 in relation to their trading and property income chargeable to Income Tax and Class 4 National Insurance contributions, if their total qualifying income from these income sources for a tax year exceeds £30,000</li></ul>They will:<ul><li>keep their records digitally</li><li>provide digital quarterly updates</li><li>be able to provide their ITSA return information to HMRC through MTD compatible software</li></ul>

Yes.The Ftax team are working on a low-cost MTD ITSA&nbsp;solution that is fully compliant with HMRC requirements. We are trying to make this as simple and clear as possible. We will make it easy for clients to exchange income and expense data with their agents, and also make it easy for the self-employed and landlords to file their own returns using ITSA.If you have any questions or suggestions then please <a href="https://www.ftax.co.uk/contact">contact us</a>.&nbsp;We appreciate your feedback as it will help us design a service that meets your needs.

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