Google Calendar is down and not working for users in the UK, Europe and the US. The problems began in the mid afternoon (BST) of 30 June and are now being investigated by Google.
The search giant's own status page acknowledges the problem with the following message: "We're investigating reports of an issue with Google Calendar. We will provide more information shortly.
Users of Google Calendar see 'Server Error' page intermittently."
DownDetector, a website used to monitor the state of popular websites and log complaints when they aren't working properly, states Calendar has been having issues since 2:48pm.
Many users from the UK, France, Germany and Italy, as well as New York and San Francisco in the US.
The server outage is not just affected consumers, but Google's business customers too, who use Calendar, Gmail and other Google service to run their companies and manage employee schedules.
It was reported earlier that Google Hangouts was also down, but at the time of publication this problem appears to have been fixed.