Computer problems prompted United to ground flights at airports around the U.S. Wednesday morning, throwing travelers' plans into disarray. After a nationwide ground stop that lasted more than an hour, the airline says it has fixed the problem is bringing its systems back online.

Update at 2:30 p.m. ET: 'Issue With A Router'

Providing more details about the problem, United says: "An issue with a router degraded network connectivity for various applications, causing this morning's operational disruption. We fixed the router issue, which is enabling us to restore normal functions."

Our original post continues:

The Federal Aviation Administration issued a ground stop order for all U.S. airports at 8:26 a.m. ET Wednesday, stating that the order was made at the airline's request. The reason given was "automation issues" — echoing the computer problems that grounded United flights one month ago.

The FAA lifted the ground stop at 9:47 a.m. ET, stating that the problem had been fixed.

United's Twitter feed features many responses to unhappy travelers this morning, apologizing for delays and promising to help.

After United's last nationwide ground stop that occurred on June 2, the Quartz website wrote:

"Aboard a New York-bound flight in Los Angeles this morning, the pilot told passengers that the computer system was 'a complete mess,' according to a Quartz reporter who was traveling on the flight, and that the plane was grounded because they were getting faulty flight clearances."

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