The Internal Revenue Service has arranged to pay Microsoft extra money to continue to support its old Windows XP computers beyond the cutoff date that Microsoft has imposed for supporting the old operating system.

Microsoft ended support for the operating system last week, sending out the final set of security patches for XP users. However, due to budget cuts, the IRS has not yet been able to upgrade approximately 58,000 of its 110,000 Windows desktop and laptop computers to Windows 7. The agency told the technology publication Computerworld last week that it will be paying Microsoft less than $500,000 for continued support after the official phase-out as part of a $30 million migration to Windows 7.

At a recent congressional hearing on the IRS’s budget, IRS commissioner John Koskinen was asked about the money it was spending. House Financial Services Committee Chairman Ander Crenshaw, R-Fla., challenged Koskinen about the extra costs the agency would be incurring.

“Now we find out that you've been struggling to come up with $30 million to finish migrating to Windows 7, even though Microsoft announced in 2008 that it would stop supporting Windows XP past 2014,” said Crenshaw at the April 7 hearing. “I know you probably wish you'd already done that.”

Koskinen agreed it was a high cost but added that it was necessary. “You’re exactly right,” he responded. “It’s been some time where people knew Windows XP was going to disappear. … Windows XP will no longer be serviced, so we are very concerned if we don’t complete that work we’re going to have an unstable environment in terms of security.”

At the hearing, Koskinen initially seemed to agree with the $30 million figure for continuing Microsoft’s support for XP, noting that it would come out of the IRS’s enforcement budget. But the IRS later clarified to Computerworld that it would actually be paying less than $500,000 to Microsoft for continued support of the retired operating system, known as Custom Support. The rest of the $30 million will be used for buying new PCs when necessary and for labor costs to complete the migration to Windows 7.

Koskinen also told the committee that the IRS had to put $300 million in technology improvements on hold because of budget cuts.