FRANKFURT, Sept 18 (Reuters) - Microsoft's free email services Outlook.com and Hotmail suffered an outage across Europe on Monday, preventing users from sending and receiving emails for 12 hours.
The outage began at 0720 GMT and continued to affect users across the region nearly 12 hours later, Microsoft said in a blog post on its Office 365 security site.
Microsoft said it was working to resolve the glitch and would issue an update later on Monday on the status of its services.
"We're continuing to investigate to determine the source of the issue and to identify service recovery steps," the firm said.
It said the issue involved part of the company's internet traffic load-balancing system which was gobbling up server capacity despite no apparent increase in user traffic.
Outage reports were concentrated in Western Europe and Britain, according to DownDetector.co.uk, an outage reporting site. No other major Microsoft online services appeared to be affected.
Reporting by Eric Auchard; Editing by Edmund Blair