Lloyds Banking Group has set up a task force to investigate the potential mis-selling of 'guaranteed' and 'capital-protected' bonds between 2007 and 2012.

Lloyds is reviewing a sample of sales of Scottish Widows products, including the Extra Income & Growth Plan (1, 2, 3 & 4), the Protected Capital Solutions Fund 1 (PCSF1) and the Capital Protected Fund 5 (CPF) which were sold in 2007, before the credit crunch which saw capital markets collapsing across the world.

SRP data shows that the PCSF1 returned 101.34% at maturity, while the CPF returned only the capital invested. The four tranches of the Extra Income & Growth Plan, a three-year reverse convertible linked to a basket of 30 FTSE100 shares, also provided low returns at maturity.

The bank has admitted that 25% of the complaints were justified, and that a "full review" was being conducted.

"We are conducting a full review of the complaints the Daily Mail has sent to us regarding the sale of structured products between 2007 and 2012," a Lloyds Banking Group spokesperson told SRP. "We strive to deliver fair outcomes for all our customers and are assessing each case on an individual basis."

A special Lloyds complaints team will review those products with low returns and will focus on investors who were in or near retirement; had never invested in the stock market before; were pursued by sales staff after receiving a cash windfall; or were told to invest a large portion of their life's savings.

Investors found to have been mis-sold products will be reimbursed for lost interest, according to the returns they would have earned in an ordinary cash savings account.

The Lloyds review follows the submission of a dossier of mis-selling complaints by the Daily Mail to the bank, suggesting that there had been widespread mis-selling in the bank's branches to customers in their 60's and 70's.

According to the dossier, Lloyds had promised 100% capital protection and returns of up to 75%, which had not materialised when the products reached their maturity.

Lloyds Banking Group offloaded its mass market investment advice service last September, and now offers advice only to customers with more than £100,000 to invest.

Lloyds was fined £1.9m by the UK Financial Services Authority (FSA) in 2003 for mis-selling the Scottish Widows Extra Income and Growth Plan (EIGP) in four tranches, between October 2000 and July 2001.