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During the process of looking into the claims issue, a VA information technology specialist found that 56,000 veterans who submitted a request to update their dependents -- adding or removing spouses or children -- "did not have those claims successfully processed by VA.gov," an error that may date as far back as 2011 and could affect their monthly benefit payments.

The agency first began investigating that issue in August 2021, but the "full scope and urgency of the problem wasn't understood" until August and the recent review of the system for the PACT Act appeals issue, Hayes said.

Work was underway Tuesday to identify all veterans affected by the notice of disagreement problem and contact them to ensure they are able to submit their appeals dated to their initial appeal date.

The agency is also working on a fix to the problem with dependent updates to make sure no more veterans are affected, and to identify those who were, Hayes said, and adjust their benefits payments as needed.

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"We will ensure that all underpaid veterans receive the full backdated benefits they deserve, and that no veterans are negatively impacted by our error," he said.

"We at VA deeply apologize to all impacted veterans, and we are working urgently to identify them, contact them, and ensure that they get all of the benefits and appeals decisions that they deserve," Hayes added. "In both cases, VA has confirmed that we will be able to identify and contact all impacted veterans and ensure that they are not further impacted in any way."

According to the VA, more than 574,000 veterans filed a dependent status update -- VA Form 686c or VA Form 21-674 -- through the VA.gov or eBenefits website or elsewhere since 2011. Of those, the VA is investigating 56,000 to make sure proper adjustments were made.

Some veterans may be owed backdated benefits, while others may have been overpaid. Agency officials said they would not request reimbursement for those who have received excess benefits.

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The announcement follows a series of issues with the VA.gov website that have affected VA disability claims. Last month, roughly 32,000 veterans received letters notifying them that claims submitted through the website weren't processed, with the error dating back to 2018 for some.

Recipients were told that the VA was conducting a thorough review of the issue and they did not need to take any action. But they were advised to pay attention to their mail for future requests from the VA for additional information, as needed.

Earlier in August, the department chose to extend a filing deadline for veterans to apply for retroactive disability compensation claims under the PACT Act after a surge in applications overwhelmed the department's online filing portal, resulting in roughly 20% of applicants receiving error messages.

In April, the department halted all future deployments of a new electronic health records system, built by Oracle Cerner, as a result of problems experienced by the handful of facilities that use it, such as safety issues involving patients and providers encountering difficulties using the system.

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The Oracle Cerner Millennium system is used at the Mann-Grandstaff VA Medical Center in Spokane, Washington, and its affiliated clinics; the Jonathan M. Wainwright Memorial VA Medical Center and clinics in Walla Walla, Washington; the VA Central Ohio Health Care System; and the Roseburg VA Health Care System and VA Southern Oregon Rehabilitation Center and Clinics in Oregon.

VA officials said they have taken steps to prevent additional issues with their information technology systems, beginning with a full review of VA.gov processing systems, looking at every place veterans submit applications and claims.

The department is creating new technological measures to flag any claims that are not processed correctly so they can be addressed. The system also will notify VA leaders of the issue. And it is investigating the bug on the notice of disagreement forms to figure out why it was not caught earlier, according to the department.

The VA has faced long-standing challenges with its aging information technology infrastructure, and its fiscal 2024 budget request seeks to continue a years-long modernization effort. It proposes $6.4 billion for the Office of Information Technology to continue to upgrade its aging IT infrastructure and services, and $1.9 billion to convert to a new electronic health records system.

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VA officials said the department continues to invest in modernizing the claims processing to improve service for veterans.

"We will resolve these issues, prevent them from happening in the future, address them more quickly when needed, and -- most importantly -- make sure that all impacted veterans get the benefits and service that they deserve as quickly as possible," Hayes said.

In 2022, the VA processed more than 1.7 million disability compensation and pension claims. As of early August, the number of pending claims totaled 1,043,961 -- with 274,148 considered to be "backlogged," or older than 125 days.