Steve Martin is self-employed, and anxiously awaited the day he could explore his Obamacare options. He is one of many who have been disappointed with's problem-filled debut, but remains hopeful about the site's future. (The Washington Post)

The Obama administration said Sunday that it has enlisted additional computer experts from across the government and from private companies to help rewrite computer code and make other improvements to the online health insurance marketplace, which has been plagued by technical defects that have stymied many consumers since it opened nearly three weeks ago.

This expanded team has come up with new ways of monitoring which parts of the federal Web site,, are having problems and has been taking the site offline for rigorous overnight tests, according to a Department of Health and Human Services spokesman.

“Unfortunately, the experience on has been frustrating for many Americans,” HHS officials said in a blog post Sunday afternoon, acknowledging what has been obvious to millions of insurance seekers who live in the three dozen states relying on the federal exchange. For the first time, the administration appealed to people to report their interactions, good or bad, with the exchange, a core element of the 2010 health-care law.

Read more about the rollout of the new health-care law.

President Obama is expected to address the site’s technical problems — “troubles that he and his team find unacceptable” — at a White House event Monday to highlight the law, according to an administration official who spoke on the condition of anonymity because the event has not yet taken place.

Calculator: How much will you pay for insurance?

“I think that there’s no one more frustrated than the president at the difficulty in the Web site,” Treasury Secretary Jack Lew said Sunday on NBC’s “Meet the Press.”

The remarks Sunday, and Obama’s expected comments Monday, represent a slight strategic shift for an administration that has repeatedly refused to say publicly exactly what is wrong with the site or what is being done to fix it. The new tack offers a bit more information while allowing officials to strike a sympathetic tone toward consumers exasperated by their experiences.

Even now, administration officials are declining to disclose many details about the debugging effort. They will not say how many experts — whom they describe as “the best and the brightest” — are on the team, when the team began its work or how soon the site’s flaws might be corrected. Still, in talking about the repairs, administration officials for the first time conceded that the site’s problems extend beyond well-publicized front-end obstacles, such as with setting up a personal account.

Since the exchange opened, officials at the White House and HHS had until now insisted that the site’s problems were caused primarily by its popularity — that more people were trying to get on than could be accommodated at once. Even Sunday, the HHS spokesman said the “main driver of the problems is volume.”

Yet insurance companies, consumers and health policy experts have noticed problems that occur further along in the process of using the exchange. The Web site sometimes gives inaccurate information about the federal tax credits that will help most people pay for a health plan, they say. And it sometimes erroneously tells low-income people that they are not eligible for Medicaid.

The exchange also is having trouble handling applications from people who are offered coverage through their jobs but could find better or less-expensive health plans through the new marketplace. Although the exchange is designed primarily for Americans who lack access to coverage through their jobs, it also may be used by workers whose employer-sponsored insurance would be too skimpy or expensive for them. Reports have surfaced that the exchange is not able to process applications from such employees.

Separately, insurers have complained that they are getting confusing information about who has signed up, with the exchange generating data that suggest multiple enrollments and cancellations for the same person on the same day.

With such issues arising, the administration is facing intensifying pressure to be more forthcoming. Some of the pressure is practical. With’s problems lingering beyond the initial days, no one knows whether the Web site’s troubles might be deterring Americans who need insurance. That raises concerns that the frustrations may discourage healthy people, who may be less motivated to sign up in the first place. Because they need relatively little medical treatment, these healthy enrollees are crucial to ensuring the financial stability of the insurance marketplace.

There is political pressure as well. The administration is eager to rebuff fresh assaults by congressional Republicans, who have been trying to undermine Obama’s signature health-care law since its enactment 31 / 2 years ago. The GOP’s last major strategy — forcing the recent government shutdown in an effort to unravel the law — failed. With the government back open, Republicans are trying to make the case that the exchange’s technical defects are evidence that the law is misguided.

On Thursday, the House Energy and Commerce Committee plans to conduct a hearing on the exchange’s rocky debut. Republicans are calling for the ouster of HHS Secretary Kathleen Sebelius, who has indicated that she has a schedule conflict that prevents her from appearing at the hearing. HHS officials say they are trying to cooperate with the committee in other, unspecified ways.

The Republican naysaying has taken on new significance now that the exchange has been launched. The Affordable Care Act requires most Americans to carry health insurance, starting in January. And the new insurance marketplaces — the one run by the federal government and the 14 others operated by states — are intended as the primary way to make coverage more available and affordable for many of the nation’s uninsured. Federal estimates have suggested that 7 million Americans may sign up in the first period of open enrollment, which extends until March 31.

The administration has not released data on how many people have enrolled through the federal exchange; officials say they will disclose initial figures in November. The administration has said that nearly a half-million Americans have filed applications for insurance through the federal and state exchanges. Applying is an early step in the process, in which people submit, for instance, information needed to determine whether they qualify for federal subsidies. Only after their applications are accepted can they shop for health plans in their areas and go on to enroll in them.

The HHS spokesman said that, as of Saturday, 19 million people had looked at the exchange since it opened on Oct. 1. That compares with 8.6 million who visited the site in its first 31 / 2 days.