A subpostmaster who was sentenced to three years in prison has said he supports a “blanket” exoneration of all those convicted in the Horizon IT scandal.

Senapathy Narenthiran, 68, was sent to prison in 2008 after Fujitsu accounting software showed a £275,000 shortfall at the post office where he worked in Walthamstow, north-east London.

Mr Narenthiran said all those convicted because of shortfalls identified by the Horizon IT system should have their convictions quashed, after the High Court ruled in 2019 that the software contained a number of “bugs, errors and defects”.

He told the PA news agency: “The conviction has to be wiped off from all their names, because the fault of the computer was proven at the High Court.

“From that day onwards, every subpostmaster who had a shortfall has got to have a blanket wiping of their criminal record. It’s not our fault this happened, it’s a fault of their computer system.

At the end I gave up and told them that if you want me to write a letter, just dictate what you want and I will sign it, as long as you leave my wife and my family alone

“It’s not the compensation we are after, we just want our names to be cleared.”

The Government has said blanket legislation to exonerate subpostmasters convicted in England and Wales will be introduced within weeks.

Prime Minister Rishi Sunak said they were victims of “one of the greatest miscarriages of justice in our nation’s history”.

Mr Narenthiran said his criminal record meant he was refused a visa to visit Canada, adding that the conviction had affected his “self-respect”.

He said: “A criminal record hanging over your shoulders affects your future as well – this is why it has to be wiped from our names.”

Mr Narenthiran said his conviction has not yet been quashed because he signed a confession under “duress” from Post Office auditors.

Mr Narenthiran, who moved to the UK from Sri Lanka in May 1985, said: “They put me under four hours of interrogation and threatened me with all sorts of things – sending my wife to prison and kids to social care.

“At the end I gave up and told them that if you want me to write a letter, just dictate what you want and I will sign it, as long as you leave my wife and my family alone.

“It threw me out of my comfort zone because I’d never been to the police station or stopped by police or anything during my career in the UK and my whole life.”

Mr Narenthiran spent one and a half years at Wandsworth, Canterbury and Standford Hill prisons, and now lives in Ramsgate, Kent.

He said: “It was very hurtful. But you’ve got to live your life. So I just carried on.

“I’m trying to establish myself back to where I was when I came to this country in 1985.”

He said he had watched the ITV drama, Mr Bates Vs The Post Office, which highlighted the scandal, earlier this month, adding that it had “brought to life” the suffering of subpostmasters.