Microsoft Corp (MSFT.O) said on Wednesday it was investigating a networking issue that impacted multiple services including Teams and Outlook, with outage reports saying the platforms were down for thousands of users globally.

Microsoft did not disclose the number of users affected by the disruption, but data from outage tracking website Downdetector showed more than 3,900 incidents in India and over 900 in Japan. Outage reports also spiked in Australia, Britain and the United Arab Emirates.

During the outage, most users were unable to exchange messages, join calls or use any features of Teams application. Many users took to Twitter to share updates about the service disruption, with #MicrosoftTeams trending as a hashtag on the social media site.

Microsoft Teams, used by more than 280 million people globally, forms an integral part of daily operations for businesses and schools, which use the service to make calls, schedule meetings and organize their workflow.

Among the other services affected were Microsoft Exchange Online, SharePoint Online, OneDrive for Business, according to the company’s status page.