I thought it didn't have to be taxing?

OK, so it’s not on the scale of the lost CDs exactly, but… this morning I got a letter from HMRC telling me that I’ll have to fill in an annual tax return. The thing is, it’s not the first letter I’ve had from them recently on such a subject.
They initially wrote to me before Christmas to tell me I no longer needed to submit a tax return. Then they wrote again to say I did. Then they wrote again to say I didn’t. Now this morning, they’ve written to me again to say I do. The thing is, I’m a company director. They know this, and Companies House knows it. And that’s one of the criteria which requires you to submit an annual tax return, no matter what.
HMRC has a real credibility problem as it is, and this sort of trivial stupidity isn’t helping. Nor is the fact that a large chunk of their website – basically anything from the VAT / Customs & Excise side, by the look of it – still doesn’t display properly in Firefox. Is it any wonder, as reported by Westmonster, that a majority of the British public doesn’t want inter-departmental data sharing?