The High Court in Dublin has appointed permanent administrators to Quinn Insurance.
It follows a dramatic turnaround by the company on Thursday when they dropped their objection to the appointment of administrators.
Quinn Insurance had been in temporary administration after the Irish Financial Regulator raised concerns about its solvency levels.
The group's owner, Sean Quinn, had been highly critical of the move.
In court on Thursday, Mr Justice Nicholas Kearns said the administrators Paul McCann and Michael McAteer of Grant Thornton, could act independently of each other if needed.
He said they would carry on the business as a going concern with a view to placing it on a sound commercial footing.
The court was told that "considerable progress" had been made between the parties since the matter was last in court on Monday.
In a statement, Jim Quigley, chairman of Quinn Insurance Ltd, said the decision was taken "after very careful consideration".
"We have concluded that, given what has happened, it is in the best interests of the company, our employees and policyholders that, as a matter of urgency, we work closely with the administrators and the Financial Regulator to get the situation resolved as quickly as possible.
"In particular, we would hope that working together we can find a way to re-commence business in the United Kingdom," the statement said.
The regulator said the High Court decision was in the best interest of policyholders.
"QIL (Quinn Insurance Ltd) remains able to pay claims and renew policies in the normal way in the Republic of Ireland and continues to settle claims in the UK," the body said.
It said investigations were continuing into guarantees offered by Quinn Insurance on the group's wider debts - the company owes 1.2bn euro and the family 2.8bn euro.
Staff, who have staged a series of rallies since the regulator moved in two weeks ago, have now said they are in favour of administration.
"We believe that, for all of us as employees, it is vitally important that we give our full support to the administrative process in order that the business and jobs at Quinn remain viable," they said.
"We believe the immediate concern for the administrator is to impress on the regulator the importance of the Northern Ireland and UK business."
The workers have cancelled a planned rally at the regulator's office in Dublin.
Instead, they plan to hand in a petition with 15,000 signatures to the Irish Regulator's office, along with an invitation to meet staff to discuss the status of a business plan to reopen the UK business.
Quinn Insurance has 600 staff in Enniskillen, most of whom are employed on the UK side of the business.
Their future is tied in with whether or not the regulator in the Irish Republic will lift its ban on Quinn Insurance conducting business in the UK.
A business plan for the UK operations was submitted to the regulator a week ago and the regulator has since sought greater details about some parts of the plan.
Quinn Group's owner, Sean Quinn, has warned that jobs will be lost if restrictions on insurance writing in the UK are not lifted by next week.
Ultimately, the administrators could sell the insurance company.
Michelle Gildernew, of Sinn Fein, said: "I think it is important that we spend money on retaining the jobs that we have, as opposed to losing them and spending a fortune on trying to provide alternative employment or training.
"I think this is a serious situation for the workers in Fermanagh and a very serious situation facing us all if the outcome is not good for the company."
Fearghal McKinney of the SDLP said it was positive that Quinn Insurance, the Financial Regulator and the company workforce were all agreed on the immediate way forward.
"There are now clear lines of responsibility for the company's future and the business case for resuming activities in Northern Ireland and Britain can be more easily made," he said.