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United 'Getting Back to Normal' After Computer Outage.

Tickers in this article: UAL

CHICAGO (TheStreet) -- United (UAL) experienced computer problems Thursday morning, but those problems are over.

"We're up and running, getting back to normal," a United spokesman said in an email shortly before 11 a.m. EST. He said some but not all mainline flights were impacted. United Express flights were not impacted.

The Associated Press earlier reported that a computer outage stranded United passengers in airports across the country. Some fliers waited nearly two hours to depart.

The airline has experienced various problems as it tries to integrate United and Continental operations following a merger. Over the summer, on-time arrival rates slumped. But they rebounded in September. In October, "performance was good until Sandy," a spokesman said on Wednesday.