So-called navigators helping consumers sign up for insurance are taking paper applications. The state recently added an addendum to these applications that asks for more data so navigators have to make fewer calls asking consumers for more information.

But now there's a backlog of paper applications, state officials have acknowledged. About 8,500 paper applications were pending as of last week.

"We're very focused on that," Quattrocki said. "People were in all weekend to input them. We also did outreach to get more information from people."

In an earlier flap, about 73,000 Marylanders were notified that their policies would not be renewed because they didn't meet Affordable Care Act requirements, such as minimum benefits. That prompted criticism that President Barack Obama was going back on his pledge that Americans could keep their current insurance.

Since then, CareFirst BlueCross BlueShield and Kaiser, which wrote the vast majority of those policies, have said policyholders could renew their policies for another year.

Brown, who is running for governor and has drawn criticism from rivals for his role in the online exchange debacle, has pledged a full assessment of what went wrong. The focus now, he said, is on fixing the problems.

"I will be one of the loudest voices calling for a thorough review," he said. "Marylanders deserve accountability."

A campaign spokesman for Attorney General Douglas F. Gansler, a Democrat running for governor, has accused Brown of hiding behind executive privilege in refusing to turn over emails about the exchange requested by The Sun in its public information request.

Officials in the Brown campaign said Gansler's office provides legal counsel about privilege to state agencies and that its calling for the release of the emails amounts to a conflict of interest.

Gansler's office, in a letter to The Sun, said other correspondence from the state Department of Health and Mental Hygiene might be withheld because of executive privilege. Officials have yet to decide whether to release those emails.

Baltimore Sun reporter Erin Cox contributed to this article.