A man lay dead in his flat for 15 months before his body was found.
Derek Perkins was divorced
Recording an open verdict into the death of Derek Perkins, 63, coroner Dr Nigel Chapman said he had never known a body to be undiscovered for so long.
The exact date of Mr Perkins' death is unknown, but a newspaper found near his body was dated 31 December, 2002.
The divorced father-of-two was found by council workers who entered his flat in the St Ann's district of Nottingham last month.
He had been living in the same place for more than 20 years, but would open his door to only a couple of neighbours.
They had tried to contact him but when they got no answer, they thought he had moved away.
Mr Perkins was divorced 28 years ago and cut himself off from his family, including his two sons.
His ex-wife Barbara Jacklin said the sons were upset.
She said: "The younger son keeps saying if only he had tried harder and kept going down, but if Derek didn't want to know them, there is nothing he could do.
"He can't blame himself."
Mr Perkins was 11 months behind with his council rent.
In a written statement, Nottingham City Council said they had tried to make contact during the past six months by letter, phone and visits.
It said faster rent arrears procedures should help the council investigate problems sooner.