When they gathered at the company's headquarters in Holland for an emergency board meeting on Valentine's Day, the supervising directors of international grocery conglomerate Royal Ahold NV got a rude surprise.

Cees van der Hoeven, the company's chief executive, informed them of a challenging new item on the agenda. He said James Miller, the chief executive of Ahold subsidiary U.S. Foodservice of Columbia, Md., had told him of accounting problems that meant profits had been overstated by at least $200 million, according to a source familiar with the company.

Even before the meeting, the six directors knew they were going to have their hands full. Van der Hoeven had called the special session to address major accounting problems that surfaced in early February at Ahold supermarket companies in Argentina and Scandinavia.

"You had a bunch of unrelated things coming together, with catastrophic results," said the source, who spoke on condition of anonymity. "The response was, 'This is unbelievable. How can there be something else going on?' More importantly, the response was, 'We've got to get to the bottom of this as quickly as possible.' "

The troubles at Ahold were months or years in the making, but they erupted during two weeks in February, when the world's third-largest food retailer went from being a fast-growing, respected multinational to a company whose future is in doubt. Ahold decided to force out its chief financial officer and then its chief executive. Its stock price sank by more than half. And now, while it still owns several profitable companies, including Giant Food Inc., the Washington area's largest supermarket chain, Ahold is under pressure to sell other assets to repay its debt.

How the company reacted to the revelations is under examination. It alerted financial authorities in Holland and the United States five or six days after the emergency meeting. By the end of that week, an anonymous letter was circulating in the Dutch financial community and news media, describing some of the problems at Ahold and saying the chief financial officer, Michiel Meurs, and possibly van der Hoeven were about to resign. The Dutch government is investigating whether some people who knew of the troubles in advance sold Ahold shares, particularly on Feb. 20 and 21, the last two days of trading before the company went public with the problems on Monday, Feb. 24.

The Amsterdam stock exchange is investigating whether Ahold moved quickly enough. Some Dutch watchdog groups and investors suggested that it did not. Others, however, said the company appears to have gone public promptly after a necessary initial internal inquiry.

A reconstruction of the company's behavior last month suggests that directors and executives moved on a number of fronts to contain the damage, starting around the Feb. 14 meeting. They launched investigations by bookkeeping sleuths and lawyers into the U.S. Foodservice, Argentine and Scandinavian issues. They began renegotiating with the banks, because the hole in Ahold's profits meant it was violating agreements. They worked to figure out the size of the profit overstatement at U.S. Foodservice, and finally said it could be more than $500 million.

The supervisory board also decided at the Feb. 14 meeting to inform U.S. legal and regulatory authorities as soon as possible. The original plan was to go to the Securities and Exchange Commission and U.S. attorney's office on Feb. 18, after the Feb. 17 President's Day holiday. The big snowstorm along the East Coast meant the visit was delayed until Feb. 19 or Feb. 20, however.

Most important, the company decided in that period first that Meurs would have to resign. Later it concluded that his boss, van der Hoeven, would have to go as well. Miller, of U.S. Foodservice, has said the issues outside the United States played the key role in triggering their resignations, and the source familiar with the company supported that statement. The company suspended two executives at U.S. Foodservice but left Miller in place, the source said, because no evidence has come to light that he knew of the problem before he was informed of it by U.S. Foodservice employees.

The supervisory board held two more special meetings in conference calls on Feb. 20 and Feb. 23. When the news of the resignations and problems at U.S. Foodservice and elsewhere was announced early Feb. 24 , it knocked more than 60 percent off Ahold's share price.

Euronext, which operates the Amsterdam stock exchange, is investigating whether the company satisfied its obligation to disclose market-moving information "as soon as possible."

An Ahold spokesman said this month that the company did "no less and no more than what was appropriate. We informed the authorities when we had an issue. We informed the market when we had something definitive to disclose." The company declined this week to comment on other aspects of the case.

Paul Frentrop, director of the Dutch branch of Deminor, a European corporate-governance consultancy, said the company should have made public each problem as it arose, rather than all at once. "Each of these things is sensitive stock price information and should have been disclosed immediately," he said.

Rob Horn, head of sales at brokerage Oyens and Eeghen, criticized the Dutch Authority for the Financial Markets for its handling of the matter. The government agency was informed of the problems on Feb. 20, but its only action was to remind Ahold of its disclosure obligations. "In my opinion the regulator was asleep," Horn said.

A more lenient view was expressed by the Dutch exchange operator and by a leading shareholder rights activist and Ahold critic.

"It's not realistic to say, the moment the CFO hears of the problem, he should issue a press release right away. He needs to find out more about what happened, how big is the problem," said Robert Bakker, manager of press relations at Euronext Amsterdam.

The exchange's inquiry into whether Ahold waited too long will take several months, Bakker said.

"I'm not convinced they were waiting too long" before making the Feb. 24 announcement, because it takes a substantial amount of time to research such issues, said Pieter Lakeman, chairman of the Foundation for Investigation of Business Information. The Dutch corporate watchdog group has criticized Ahold's handling of other issues and asked Euronext to investigate a delay by Ahold last summer in disclosing information about problems in Argentina.

The accounting irregularities at U.S. Foodservice are Ahold's biggest problem because they affected earnings in a material way. The trouble was with purchasing allowances or rebates paid to the company by suppliers. There were gross discrepancies between the amount of money taken in and what was reported on the company's books.

The firm suspended Mark P. Kaiser, U.S. Foodservice's chief marketing officer, and Tim Lee, a purchasing executive. Their boss, Miller, told van der Hoeven about the problems on Feb. 12 or Feb. 13, and said he previously "had no idea there were ongoing irregularities at all," the company source said.

Ahold's problems with its Argentine subsidiary, the Disco supermarket chain, date back some time. Ahold bought the unit in phases from the Peirano family, several members of which are now in jail in Uruguay. In July, Ahold said it was taking over $492 million in debt from a company controlled by the Peiranos. Argentine newspaper reports have suggested that the accounting treatment of the debt may have been manipulated.

On Feb. 24, Ahold announced that it was investigating possibly illegal transactions at Disco. Three days later it said it had completed the investigation, and that Disco's chief executive and three other top officials had resigned.

The issue at the Scandinavian unit, ICA Ahold, in which Ahold holds a 50 percent interest, had to do with how Ahold accounted for its results. Ahold had been treating the results as if it had a controlling interest, which enabled it to report higher total sales than it would have otherwise.

But Ahold has said information was not provided to its outside auditor, Deloitte & Touche, which affected how the results were reported. Deloitte is said to have uncovered information in the year-end audit that showed that Ahold did not have a controlling interest in the subsidiary and thus had to report its results differently.

Henny de Ruiter, chairman of the Ahold supervisory board, said on Dutch television this week that it was an accumulation of problems that led to the ouster of Meurs and van der Hoeven.

"There was not one trigger. . . . Two profit warnings, questions over consolidation, problems in Argentina, then came U.S. Foodservice," de Ruiter said. "They felt that they had lost the trust of the financial markets and it was in everyone's best interest to leave."