The Central Bank has prohibited the former assistant manager of the now liquidated Rush Credit Union from working in any regulated financial service provider for an indefinite period of time.
Liquidators were appointed to Rush Credit Union in November 2016 after financial irregularities were discovered.
Deficiencies uncovered included control of cash, lending practices and the day-to-day running of the credit union.
Other issues included car draws where no winners were announced. Some €221,000 was spent on vehicles between 2009 and 2016.
The Central Bank said it was prohibiting Geraldine Harford from carrying out any controlled functions, including pre-approval controlled functions, in any regulated financial service provider for an indefinite period.
The move comes after a Central Bank investigation into Ms Harford's involvement in unauthorised transactions on accounts at the credit union in north Co Dublin.
Last year, the Central Bank said the former manager of Rush Credit Union, Anne Butterly, was also prohibited from carrying out any management functions in any financial services firms.
Seana Cunningham, the Central Bank's Director of Enforcement and Anti-Money Laundering, said today's prohibition notice has been issued pursuant to the Central Bank's fitness and probity regime following its investigation into financial irregularities at Rush Credit Union.
"The prohibition of individuals for an indefinite period of time from performing specific roles in financial firms is the most serious outcome under the fitness and probity regime," Ms Cunningham added.
"It is imperative that individuals in positions of responsibility in financial services firms are committed to and demonstrate the highest ethical standards of practice and behaviour," the Central Bank director said.
"This latest prohibition notice demonstrates that when individuals working in financial services firms do not comply with the Central Bank's fitness and probity standards, the Central Bank will take action," she added.
This is the fourth prohibition notice issued by the Central Bank since its introduction.