Yorkshire Bank - Default logged with Experian

sdm270574

Just over six years ago Yorkshire Bank interest charges took me over my limit leading to further daily charges that amassed. THey subsequently closed my account without me paying what I "owed" them. I understand that I will not be able to claim these charges back as it is too late but i would like to get rid of their "default" log on my credit record. This log shows :

my personal details
DEBT ASSIGNED 02/06
YOrkshire Bank Current Account
Started 22/12/00 Default £99 Defaulted 08/12/03 Balance Satisfied
Status History 8
File updated for the period 05/02/06

Shortly before the 6 year period was up they started chasing me again for the amount after a hiatus of a few years. I imagine it was because they knew they were running out of time. I looked into challenging them but in the end let it ride as I assumed they would be unable to claim back after 6years was up, the debt would disappear and my credit record clear. Not so, according to the above the default is dated 8th Dec 2003 leaving me nearly four years with it on my record. How do I go about removing this from the records if I am no longer in a position to claim an amount of money by threatening court proceedings?
Thanks in advance!