Yeah, Experian are a **** nightmare to leave – they make their money selling dubious services to people who don’t really understand how credit reporting works – which is like saying they rip off people who don’t understand Rocket Surgery, there’s acres of bullshit written and spoken about credit reporting to make it seem more complex than it is.
Anyway, due to the DPA Credit Agencies can only hold data for a maximum of 6 years from the month it’s filed so they won’t be able to help you with anything prior to this.
Also Banks / Building Societies aren’t required to hold data for more than 6 years – I know for a fact that one of the big banks has data going back to the 1800’s (obviously some of it’s archived in less than easy to access forms) but a lot of this is ‘de personal-isd’ I.E. they keep the raw data for use, but removal all the customer names.
To claim a missold PPI claim from more than 6 years ago you would have to have the paperwork, or at least remember the details and contact them and hope they’ll fess up about having the details of it.
By all means dig though your paperwork at home, but Experian can’t help you.