WASHINGTON (CBS DC/AP) — Millions of Americans have logged onto the Healthcare.gov website since it’s Oct. 1 launch, but glitches on the websites have kept many from actually signing up, and has computer experts saying the technology needs a complete overhaul.

The Obama administration promised “significant improvements” in accessing the federal health overhaul website this week, after taking down the system for maintenance. But many were still unable to enroll.

The administration has refused to release the numbers for how many have signed up and media outlets have struggled to find people who have actually signed up.

Health and Human Services Secretary Kathleen Sebelius said Tuesday during a meeting in Tampa that programmers are taking the website down at night, during periods of low use, in order to fix the technology flaws and update software.

“We are working really around the clock,” she said. “We have made a lot of progress. Today is better than yesterday and we’re hoping in the very near future to have a seamless process.”

However, CBS News reports that tech experts see major flaws, and one online programmer said he would be “ashamed” and “embarrassed” to have produced the health care website.

“It wasn’t designed well, it wasn’t implemented well, and it looks like nobody tested it,” Luke Chung, an online database programmer, told CBS News.

“It’s not even close. It’s not even ready for beta testing for my book. I would be ashamed and embarrassed if my organization delivered something like that,” he said.

President Barack Obama and his staff have downplayed the technology flaws and said delays reflected the public’s huge interest in the website. There were 7 million visits to HealthCare.gov in the first two days. But federal health officials acknowledged problems beyond just high web traffic.

“The volume actually identified some additional features,” said Sebelius. “We’re a week into a 26-week process. I am confident in the very near future that we will have it flowing smoothly.”

Technicians were adding equipment to expand the site’s capacity and making software changes that had already cut wait times in half since Friday.

Experts said the decision to require that consumers create online accounts before they can browse available health plans appears to have led to many of the program’s technical problems. Consumers trying to create their accounts multiplied the volume of online transactions that have overwhelmed the website.

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