MONTPELIER, Vt. (AP) -- After spending six years and more than $18.5 million to modernize computer systems at the Vermont Department of Motor Vehicles, the state is scrapping the effort, officials announced Wednesday.

Top aides to Gov. Peter Shumlin said the state and computer giant Hewlett-Packard had agreed that HP would return $8.37 million to Vermont and that Vermont would return to the company all "physical and virtual rights to all software and documents created by HP" to build a system that has been in the works since 2006.

"It's a no-fault divorce," said DMV Commissioner Robert Ide, "a realization by both sides that this relationship is not going anywhere."

HP is the fourth vendor on the contract, after a series of corporate takeovers that culminated with HP buying Electronic Data Systems. HP spokeswoman Ericka Floyd did not immediately respond to a request for comment.

Under its agreement with the company, Vermont will pay $262,000 to HP for a point-of-sale system that enables DMV clerks to enter customer transactions into the state system, Ide said. But he said that represents just a small fraction of the system upgrades that were envisioned when the state launched the effort in 2006 to modernize then then-30-year-old DMV computer system.

Ide and Jeb Spaulding, the state secretary of administration, said the biggest lost to Vermont taxpayers likely is the nearly $5 million in state staff time DMV employees have put into trying to implement system changes that now are deemed to have failed. Other unreimbursed state expenses include money Vermont spent for "change management consulting" and other services, they said.

Ide, who became commissioner in 2009 as the project was already under way, said he does not plan to shop for a new vendor immediately.

"I'm going to be working with my crew here to keep our existing system working and running," he said. Ide said that states from Rhode Island to Arizona had experienced similar problems, and that he wants to wait to see another state making a successful systems upgrade that Vermont may be able to replicate.

After another state is successful, "Then perhaps I'd have the time and energy to go across the street and ask for money" from the Legislature to start the process anew. He added, "My people need a break. It's been incredibly discouraging for our people who were working on this project."

While the struggle has caused internal difficulties, Ide said he did not believe customer service at the DMV had suffered. The DMV's current system has not been out of service a single day since he got there in 2009, Ide said.