Many carriers were brought to their knees yesterday due to a software outage at technology company Microsoft. Some of the world’s largest carriers have canceled flights, planes grounded, and are reverting to old-school techniques to check-in and board aircraft. However, the world’s largest low-cost carrier, Southwest, has been able to power through due to an operating system that is 32 years old. Dallas-based Southwest Airlines was unaffected yesterday by the Microsoft outage that has plagued carriers in every corner of the globe. This is due to the airline working from Windows 3.1, a version that was first released in April 1992 as the successor to Windows 3.0