CHICAGO (AP) - Computer glitches frustrated more Americans checking out their options under President Barack Obama's health care law, and administration officials said Wednesday the problems are mainly due to high consumer interest, not hidden flaws.

The Health and Human Services Department issued survival tips for aggravated consumers after 4.7 million unique visitors logged in to the healthcare.gov website on Tuesday. As new health insurance markets went live around the country, the federal call center also received 190,000 calls.

Agency spokeswoman Joanne Peters said people who find themselves at a "holding page" when they first get on the website should not hit the refresh button or leave that page. If they do, they will lose their place in line.

Peters also reminded consumers that they have until Dec. 15 to sign up if they want coverage to start Jan. 1.

"While this overwhelming interest is continuing to cause wait times, there will be continuing improvements in the coming hours and days," she promised. But the government still isn't saying how many people have succeeded in getting through the process and signing up for insurance.

The debut of insurance marketplaces might have been a victim of the law's own success. The initial sign-up day appeared to draw heavy interest that suggested pent-up demand for just the kind of coverage now being offered.

Tennessee State University student Sam Rutherford, 31, said he signed up for a policy on Tuesday, some 15 years after a sledding accident that resulted in him losing several organs.

"I've been virtually uninsurable since that time," he said.

In 36 states where the federal government is running the marketplaces, a snag involving security questions on users' accounts cropped up repeatedly, preventing many from completing their enrollment.

Brett Graham, a consultant advising states, called that glitch "a real show-stopper."

" If you can't set up an account ... you can't enroll," said Graham, of Leavitt Partners, a consulting firm run by former Health and Human Services Secretary Michael Leavitt, who rolled out the Medicare prescription drug benefit under former President George W. Bush.

The government said Wednesday the problem is due to a high volume of users, not a programming glitch. Around the country, people using the federal website said they were still getting stuck on the page.

In some states, trained health care guides resorted to old-school means of signing people up: paper or telephone.

Katie League, an outreach and enrollment manager at Health Care for the Homeless in Baltimore, used paper applications to register people when the website developed problems. She said she wasn't surprised by the opening delay and took it in stride.

"Today is the start of preseason," League said. "You know, not every quarterback is ready on the first day of preseason."

Officials in President Barack Obama's administration said they are pleased with the strong consumer interest, but on a day of glitches they refused to say how many people actually succeeded in signing up for coverage.

The technical trouble couldn't dampen the relief Hussein Daoud felt for himself, his wife and their six children.

The 51-year-old Detroit man came to apply for insurance at the Dearborn-based nonprofit organization ACCESS. With the help of counselors, he learned that his annual income of $14,500 made him eligible for Medicaid, and he likely won't have to pay for a plan that covers his family.

"This is the first time I asked for anything from the government, and I'm really glad that the government can help my family," said Hussein, who lost his supervisory job at a dollar store when it closed a few years ago. He now sells used cars and can't afford health care coverage.

Minnesota got its site running after a delay of several hours. Rhode Island' s site recovered after a temporary crash. A spokesman for the New York Department of Health blamed difficulties on the 2 million visits to the website in the first 90 minutes after its launch. Washington state's marketplace used Twitter to thank users for their patience.

Exchange officials in Colorado said their website would not be fully functional for the first month, although consumers will be able to get help applying for government subsidies during that time. Hawaii's marketplace wasn't allowing people to compare plans and prices.

Connecticut seemed to be a bright spot. Access Health CT sent out a tweet shortly before noon Tuesday, confirming the marketplace logged 10,000 visitors in the first three hours of operation and 22 enrollments.

California, home to 15 percent of the nation's uninsured, reported delays online and on the phone because of heavy volume.

Some of the excitement surrounding the opening of the marketplaces was tempered by dismay over the government shutdown led by congressional Republicans who want to block the insurance reforms.

But the shutdown will have no immediate effect on the insurance marketplaces, which are the backbone of the law, because they operate with money that isn't subject to the annual budget wrangling in Washington.

The Obama administration hopes to sign up 7 million people during the first year and aims to eventually sign up at least half of the nearly 50 million uninsured Americans through an expansion of Medicaid or government-subsidized plans.

Many states predicted that an initial surge of interest would test the online system, but they expect most people to sign up closer to Dec. 15, which is the deadline for coverage to start Jan. 1. Customers have until the end of March to sign up in order to avoid tax penalties.

Under the law, health insurance companies can no longer deny coverage to someone with a pre-existing medical condition and cannot impose lifetime caps on coverage. They also must cover a list of essential services, ranging from mental health treatment to maternity care.