Colonial Pipeline, the main Gulf Coast-East Coast artery for gasoline and other petroleum products, ran into a new computer snag Tuesday as it was still recovering from a shutdown that started May 7 after a ransomware attack.

The company said the latest problem, which interrupted the system used by shippers to place requests for service, called nominations, was not a continuation of the cyberware attack that sparked panic-buying by frustrated motorists across the Southeast last week. In a statement, the company said that the problems arose from the effort to “harden” its systems to ward off future cyberattacks.

It said that the pipeline continued to operate.

“Our internal server that runs our nomination system experienced intermittent disruptions this morning due to some of the hardening efforts that are ongoing and part of our restoration process,” Colonial’s statement said. “These issues were not related to the ransomware or any type of reinfection. We are working diligently to bring our nomination system back online and will continue to keep our shippers updated. The Colonial Pipeline system continues to deliver refined products as nominated by our shippers.”

Colonial is a privately held company owned by Koch Industries, Royal Dutch Shell and several investment firms. A Shell spokesman said Tuesday that he had no details to add to the Colonial statement. A spokesman for Phillips 66, one of the pipeline’s customers, declined to comment.

The operators of the 5,500-mile pipeline system, which runs from Texas to New Jersey, discovered they were under a ransomware attack May 7, which had infected their information system but not the operating system. To avoid losing control of the pipeline, the company said, it shut down operations.

Colonial supplies the East Coast with 45% of its fuel.

By early last week, news of the shutdown had set off a run on gasoline throughout the Southeast, and the majority of stations in several states went dry. States further to the north were less affected because they had larger reserves on hand. The price of gas nationally rose to its highest level since 2014, but it did not spike as much as some analysts had feared.

Colonial began restoring service by midweek, but it has taken several days to get the whole system back to normal. Several reports have asserted that the company paid $5 million in ransom to regain control of its computers from a group called DarkSide that appears to have been based in Russia.