KPMG was hit on Thursday night by a major outage to its systems that crippled its email servers.
The global consultancy firm, which restored functionality on Friday morning, said that the outage occurred last night in its Central American systems.
"It's back up now," said Gavin Houlgate, head of corporate communications for the company. "It was down for five to seven hours. The cause of it was a technical problem in Panama."
According to an employee on KPMG's helpdesk, the outage affected systems globally.
Houlgate denied suggestions that a virus caused the problems.
A message on the company's technical support line said that functionality had been restored to the systems, but that as a result of the outage there would be delays to email.