United Airlines grounds domestic flights because of computer issue

Posted at 8:22 PM, Jan 22, 2017
and last updated 2017-01-22 23:01:33-05
UPDATE:  United is reporting that  the ground stop has lifted.  They are working to get flights back on schedule.
Original story:
United Airlines grounded all domestic mainline flights Sunday night because of a computer problem.  
The company tweeted...
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