HM Revenue & Customs has wrongly told hundreds of thousands of people that there is a hole in their National Insurance contribution record.
The BBC discovered the blunder after a number of people contacted Money Box to say they had been sent letters in error.
HMRC has confirmed its error but cannot say how many people are affected. The Institute of Payroll Professionals estimates it to be 700,000.
We asked for your comments, a selection of which are below. This debate is now closed.
I received one of these letters and I wrote sending in a copy of my P60. Because they do not recognise that I have paid my full National Insurance, they have failed to forward the NI Contributions on to my Stakeholder Pension company in respect of my opting-out of the government's second pension. I am therefore losing investment growth, and have asked them for a date when this money (approx £1,500) will be sent and how much compensation they will pay.
Richard Proudfoot, Norwich
I sent for a pension forecast 18 months ago. I was told there was a shortfall in contributions. I telephoned, I forwarded the relevant P60s. I have requested two more forecasts in the past year and it still hasn't been corrected.
I'm stunned that this huge NI error for year 2004/2005 is still unresolved as it was known to exist at least since March 2006 as I received a state pension forecast that included this error of £371.80. When I queried it in March they said they already knew this error was present on thousands of forecasts due to errors from the Revenue systems. Yet nine months on they are still making it worse!
I haven't made NI contributions since 1995. Ironically, I haven't received a letter stating there is a shortfall for year 2004/5, which makes this situation even more strange.
I received such a letter which was dated a month earlier than the postmark. I am fully paid up for that year and no, I'm not sending an original P60 for them to lose or wasting any time filling out forms. What about other years? Am I going to reach pension age to be told "sorry love, the latest piece of technology hasn't heard of you".
Kay Adamson, Chester
I received one of these letters and just saw red. I was very angry and especially as I work in the Royal Household. Do you think my boss would not pay over NI contributions? How did these letters get out? Do we now employ brainless wonders in the civil service? Surely somebody checks what a computer system is producing? Anyway, I phoned the helpline and was rather rude. I have now sent the letter to my MP saying that I want the matter sorted out.
Ted Shepherd, Windsor
I don't suppose they'll pay any compensation, yet if we're late with filing, we face a substantial fine. As much of HMRC's work is handled by overpaid consultancies, they should forfeit a substantial portion of their fees for each and every blunder!
Neil, Devizes, UK
I work for local government and received my letter a couple of months ago. I phoned the helpline and was told that due to staff shortages, 04/05 contributions hadn't yet been input, so the computer saw the shortfall and sent out the letter. They said this affected a couple of hundred thousand people and to ignore the letter!
My colleagues at HMRC are perfectly capable of organising events at breweries. The consultants who designed the IT systems sold them to successive governments. The chancellor has said he will put an end to "consultancy culture". It would be nice if that were to include a review of the major IT consultancy and outsourcing failures up to date - but don't hold your breath. Too many skeletons in too many cupboards for the real culprits ever to be brought to book, I fear.
I got the impression that the erroneous letters are related to people on payroll. I am a full-time mother, currently in receipt of child benefit and therefore Home Responsibilities Protection. I have received a letter suggesting a voluntary top-up payment of £350, which doesn't make sense to me, as I thought the whole point of HRP was to protect against the inability to make any NI contributions whilst caring for children and out of the paid workforce. This is the first time I have received such a letter whilst in receipt of HRP.
Penny Carter, Guildford
I also received one of these letters. I was so shocked as I have been in continuous employment throughout those years and knew my contributions were up-to-date. But as a trusting person, as most people are, it didn't enter my head that the Revenue could be wrong. So I was saving to pay this money to them, but thanks to your programme I do not need to worry now.
June Arnold, Builth Wells Powys
It is not just people in work who have a problem with 04/05 National Insurance records, people who have recently retired are getting less pension then they should because they have no contributions recorded for that year. in some cases it has caused a system fault with Additional Pension payments and people are thousands of pounds down.
When the Revenue had previous IT problems the press always hammered the US owned company EDS (the previous IT contractors) for the problems. Since the contract is now in the hands of the French owned Cap Gemini, they are never mentioned when any IT problems occur. Why the unfair press? Living in the town and being an employee of one of the companies where these errors are created, I do have quite some insight into these problems.
To our company's credit (EDF Energy) they did contact nearly every employee via our payroll and have told us to contact them if we receive a letter from the Revenue. But what will the incompetent Revenue do about it and how many other "little errors" have gone unnoticed?
I work for the Foreign and Commonwealth Office and received one of these letters this week despite my contributions being up to date. I called the helpline, was put straight through to an assistant and the problem was explained to me clearly and resolved in a matter of minutes. Errors do occur but at least enquiries are being handled professionally and not by an automated system.
My flatmate received one of these and was truly puzzled. Once again a major failure to correctly implement a government IT solution. Why are these contractors paid? If they make a mistake they should be harshly punished, and if they make a perfect system they should be given bonuses.
Not only did I get the pension letter, I also was prevented by this error from getting Jobseekers' Allowance. When I eventually discovered why, I went with my P60 to prove I had paid the NI. The Job Centre staff knew all about the problem and I am still awaiting the allowance five months later.
I work for GE Capital, one of the largest companies in the world and I too have received one of these letters. I think it is scandalous that the BBC/Moneybox has to bring this to our attention. The Revenue should have immediately sent out a letter informing us of this problem.
The Revenue admitted to me there was a problem with 2004/5 back in May. My son, who used to work for me, was denied invalidity allowance because the office he was dealing with said he had no contributions for the year in question. I had paid all his contributions as I was his employer at the time. When questioned the Revenue said that payments were received and the Contributions Agency told me there was a major backlog because of new computer systems failing. He appealed but had all benefits withdrawn because of the gap.
Bob Bowen, Weston super Mare
Another IT disaster from a badly designed and badly funded IT system. This at the same time HMRC announce plans to make staff cuts because they say they now have efficient staff-saving computer systems.
This bodes well for ID cards and the NHS IT system doesn't it?
I have received one such letter, and I was confident that it was a mistake, as I keep all my records for at least three years.
S Jondhale, Birmingham
Government IT projects are initiated by ministers and senior managers in the civil service. Seasoned in-house IT professionals are not usually involved in the planning stage. We only get involved at implementation, when changes raise costs significantly and lengthen schedules. We are then often overruled as the short-term ramifications are politically unacceptable. No-one really cares about the long term, our current system simply doesn't reward long-term thinking.
Maybe if the mammoth HM Revenue and Customs was split into more focussed businesses it would be able to do its job properly. How can one director at the top be able to keep their finger on the pulse when the business is all over the place.
Richard, Milton Keynes
What about those on benefits? My wife is on incapacity benefit and she's received one of these letters.
Alan Horn, Berkhamsted
Just one word missing: "Sorry". Not surprising, though. What incompetence! What arrogance!
Income tax £4,000, National Insurance £1,800, Revenue and Customs WORTHLESS. Too much bureaucracy, rules no one (including themselves) can comprehend, and an attitude of "we don't make mistakes". It's time the entire incompetent lot was scrapped and replaced by people with brains in their heads. Let's not forget the repeated Tax Credits fiascos in addition to this latest example from this hopelessly inept agency.
Jim (Born free, taxed to death), Greater Manchester
I received one of these letters last September, and I am not in one the groups mentioned. When I rang, I was told everyone's record for the same part of that tax year was missing due to a problem with moving records between different computer systems, and they knew there was a big problem. They said that it would get sorted out over time, but until it was, more letters would be sent out. Because I phoned, my record was corrected within a few days. Since then, my wife has also received a similar letter. My advice, forget the letter, it will sort itself out. But it does make you question everything that the government and its departments are doing.
Adrian Richards, Nottingham
This error has been discovered in a timely manner. How can we be sure when we eventually come to draw our pension that the final calculation will be based on accurate records dating back some 44 to 49 years? Unless people have kept every P60 between school and retirement, the Revenue's computer's decision will be final.
Kevin Geary, Radstock
I had a similar notice last year relating to payments in 1998. It said I hadn't paid the stamps for eight months although 1998 was the same throughout. If I paid the difference I would get full pension. I then spent considerable time and trouble telling them they were wrong, with which conclusion they agreed. I still haven't had the difference or even an acknowledgement of the difference.
D Smith, Dorchester
The trouble is that the tax system is simply too complex to be computerised! Maybe they should try simplifying it before using a computer? The error is not the computers, by the way, but the overload caused by failing to appreciate how much the system would be overloaded! Most government bodies are optimists!
I work for HMRC. I can confidently state this is not a case of human error. HMRC and the NHS run two of the largest databases in the world. Staff really do try their best given the conditions and systems they have to work with, so problems will occur occasionally. People should also realise that the money given by the government to run HMRC decreases each year, reductions in staff are expected too. This has been the case for years, and will continue. There is only so far you can squeeze before the juice starts leaking!
I received one such letter - I'm a 21 year old student who hasn't actually started making pension contributions. I should imagine that I need to give considerably more than £371.
Always include a copy of the relevant, recent letter which the Revenue sent you in any query. I find it helps!
Chris Gore, Richmond
I was made aware of a 2004/05 contribution shortfall when I requested a pension forecast from the Pension Service in January. The irony is I work for HMRC! I wrote to the National Insurance Contributions Office, enclosing a copy of my P60 and it was put right. Their comment? "There is a delay in processing your employer's scheme."
The phrase "computer error" is nonsense. It is always used in a pathetic attempt to evade responsibility for a human error.
Bob Pearson, Bourne
Both my wife, a teacher, and I, a self employed IT consultant, who files end of year returns online, have been told we have to pay £370 because we are short on NI contributions for 2004/2005 which we are definitely not! I have written to the Revenue but won't hold my breath for an answer.
As a software engineer, I find the comment "they were aware of the error but they can't do anything to stop it" sadly comical. I wonder which massive consultancy got huge dollops of cash to develop this software.
This is now the third incorrect notification I have received from the Revenue in three years. On questioning them, I received a letter saying that on further investigation my records were up to date. No apology for the waste of time and effort made to try and contact them and send them proof of my payments. This completely undermines my trust in the system. No wonder the pensions industry is in such a mess.
Julia Arnott, Amptill, Beds
The BBC is a bit slow here: lots of us at work got our letters back in October! Fortunately the HMRC helpline was well-prepared (open until 8pm too). It told us it was a computer glitch and suggested that we ring back in 12 weeks if we hadn't been sent a letter saying that they had made a mistake.
Sue, Bath, Somerset
Computer blunders are very rare, it is usually the people that programme them that cause the problems.
Simon McWade, Stockport
This is just crazy especially given the fact that the numbers of years required for a full pension based of NI contributions is likely to reduce from 44 for men and 39 for women to 30 years for all. Thus making perhaps all of the 4.7 million letters completely irrelevant! Our tax system is way too complicated, combined with a chancellor making it up as he goes along. No IT system could cope.
Peter Judson, Ibstock
It's a good job HM Revenue & Customs don't run parties at breweries!
Another government IT disaster! Will anyone be held responsible and removed (downwards or out) from their post? Not a chance! Early retirement on a good pension or even promotion is more likely from this government that does so much to reward incompetence!
Mark Pearson, Bicester, Oxon
The comments we publish are not necessarily the views of the BBC but will reflect the balance of views we have received. It is helpful if contributors state if they work for any organisation relevant to an issue discussed. Readers should form their own views on whether messages published represent undeclared interests, or views prompted by a common source.