A student is appealing to the Office of the Independent Adjudicator against his PhD referral, claiming that either his supervision was inadequate or the university appointed inappropriate examiners.
The student, who does not want to be named, began studying for a doctorate in marketing at Royal Holloway, University of London in 2007.
He told Times Higher Education that he had always followed his tutor's advice and had regularly received positive feedback. But following his viva voce in January, his examiners ruled that his thesis needed to be "completely rewritten".
Under Royal Holloway's rules for referral, he has 18 months to complete the necessary changes.
The student told THE that many issues raised in the examiners' report had not been put to him during his viva, giving him no opportunity to defend himself. He claimed his supervisor had been equally bewildered by the verdict.
"This is not a matter of academic judgement but a mismatch between my academic supervision and the method of assessment which the university itself selected," he said.
The student also had several other complaints, including that the date listed on his PhD decision report form was the day before his viva. He said the university told him that this was an administrative error but he believed it implied that his fate had been decided "before I even had a chance to defend my thesis".
In a statement, Royal Holloway says its investigation of the complaints "found no evidence of any flaw in the examination process, nor any matter which would call into question [its] integrity".
It adds: "It is not uncommon for a PhD student to be asked to make amendments to their thesis at this stage, and it is not normally considered a failing of their supervision or the [exam] process when they are.
"We very much hope [the student] will take the time he has to concentrate...so that he can gain his PhD."
But the student said attempting to rewrite his thesis in the time available was a "gamble" he would not take - even though he needs a PhD to be promoted from assistant to full lecturer at the overseas university where he now works.
"I am on medication and seeing a psychiatrist," he said. "I am overwhelmed with the sense of injustice. I'm the sort of person who never complains. If I don't like a service I just go elsewhere but in this case I can't because no university will touch me now because, for them, I am a failed PhD."
He said that if the OIA would not hear his case he would take it to the courts.