Microsoft said a day-long service outage affecting the Exchange Online service has ended following hours of complaints from users about connection issues. On Monday evening, Microsoft explained that it was investigating problems with the service after users said they were “experiencing delays or connection issues when accessing the Exchange Online service.” Two hours later, the company said its traffic management infrastructure was not working and attempted to reroute traffic in an effort to end the outage. It took another nine hours before service was fully back to normal.