OK, I've changed the setting and you're welcome to PM me.

In summary, whether you need to pay tax depends on where you live, how much you've earned from your bitcoins, and perhaps (in the UK) whether they are classed as an investment or as gambling. Also may depend on whether you've mined them, and if so whether you were doing so as part of a hobby or a for-profit enterprise.

I have contacted an accountant but not yet engaged their services. I have found the contact details for HMRC but not yet contacted them myself. When I have further information I will post here again openly, in the hope that it will be of use to someone else.