1. This is your bank that checked out an investment for you and said it was good... So you then got some of your friends to invest as well and you paid all of the money to your bank to invest in this deal. The deal was then exposed as a scam??? -There would be the time to take this to court.
2. You then decided to refund your friends investment? Why? Your friends would have the same claim as you against the fraudulent investment... You have tried to do the right thing, but then immediately implicated yourself by doing this- You are a) Accepting some kind of responsibility for your friends investment, but more importantly b) Possibly defrauding the bank by obviating your investment risk to the bank through an overdraft.
3. Why would you do this through an overdraft? This is just mad, the rate of interest is far higher than if you took out a personal loan... But more importantly- You had no duty to do this if the investment was a scam.
4. If the bank demanded this back over 6 years ago they would have issued a default notice. It would be from that date of issue, and from the date of the last service of the debt (If you made any payment into the debt after Default is issued, then the date of that payment supersedes the Default Notice date).
5. Unfortunately for you, there is an increasing tendency for creditors to attach UNSECURED debts to people's property by getting a county court order and registering it with the Land Registry. The reason for this is to avoid being Statute Barred after 6 years (or 10 for Mortgage debt) This is the point that you should have appeared at court to explain that this debt is UNSECURED and should not be attached or secured. People are too scared to appear normally and so the courts just wave all requests through. You are pretty much sunk then as far as escaping it -The attachment is on your property and will show up on any land registry search if you want to sell it. And if you do sell it, then the creditor will take his amount first. -There is no time limit on the attachment and it will just sit there until you can either pay back the creditor, sell your house Etc. You may also find that your mortgage provider gets very annoyed as well- You are risking their investment as well!
6. You can go to court and have the attachment lifted if you can prove that it was wrongly attached- Good luck with that one, Or you can repay the initial debt.
Homeowners have lots more to lose in the UK when they can't/won't defend their property from creditors.