Microsoft said it’s working to resolve an outage affecting its suite of office products after thousands of users reported trouble accessing the services. As of noon Eastern time, the outage reporting site Downdetector charted more than 10,000 concurrent reports for Outlook, 365, Teams and the Microsoft store combined.

Among the hardest hit by that outage was Delta Air Lines, which claimed in a recent lawsuit against CrowdStrike that their operations were crippled for several days. Delta canceled about 7,000 flights over a five-day period during the peak summer vacation season.