The Main Reading Room of the Library of Congress. (Michael Dersin/Library of Congress)

This post has been updated.

The computer failures at the Library of Congress that have crippled the U.S. Copyright Office since last week also have shut down the electronic services of the National Library for the Blind and Physically Handicapped.

That office’s Braille and Recorded Books, or BARD service, has not worked since Tuesday, preventing thousands of visually impaired readers across the country from accessing materials.

The National Library for the Blind provided about 25 million copies of books and magazines to more than 800,000 reader accounts in 2013, according to the Library of Congress’s annual report from that year, the most recent available.

“We’re not really sure what happened,” said JD Hall, manager of the Regional Library for the Blind and Physically Handicapped in Little Rock, Ark., one of the library’s state partners. “We have backup for all the state library materials, so we can switch over to that.”

Managers of the regional and state offices say customers are calling for help because they are unable to download audio and braille files.

“I haven’t received a full explanation,” said James Woolyhand of the Florida Bureau of Braille and Talking Book Services. “This took everyone by surprise. It’s not a common thing.”

The Library of Congress scheduled system outages last weekend for routine maintenance, officials said. But when that work was complete, officials were unable to bring back several critical systems at the library, the federal agency that houses several offices, including the Copyright Office, the Congressional research and law libraries, and the national service for the blind and disabled.

After the weekend disruption, BARD was working Monday, but went down Tuesday and hasn’t worked since, Hall said.

The library didn’t include the BARD service in its initial report on which systems were shut down. On the BARD Web site, a message reads, “We regret that BARD is currently experiencing difficulties. At the present time we have disabled BARD until we can resolve the technical problem.” It says the service “will most likely be down” until late Sept. 8.

“We regret the inconvenience to our many and varied users. Efforts continue around the clock to return the affected sites to service,” Library of Congress spokeswoman Gayle Osterberg said in an e-mail.

The widespread computer failure comes five months after a scathing Congressional report found major problems with the library’s information technology systems. The report blamed Librarian James H. Billington and his executive team for mismanagement and failing to hiring a chief information officer. Weeks later, Billington announced that he would retire at the end of the year after 28 years in office.

Susan Chinault, manager of the Braille and Talking Books Library at the Michigan Bureau of Services for Blind Persons, said about 3,000 state residents have BARD accounts, about one-quarter of the state system’s patrons. She said that those who can’t get materials can have them mailed from her library.

“This is a critical failure,” she said. “For those who get magazines and for those who download directly from BARD, it’s a big inconvenience. They are very dependent on it.”

But Chinault said the state partners are aware of the technological challenges of the federal government. “We’ve always known that it takes a lot longer for the federal government to catch up,” she said. “I can have patience with them, and our patrons are not pleased about it, but it’s not a life-or-death situation.”