From Google for Work support.
RESOLVED 9/15 01:04CST: The problem with Gmail should be resolved. We apologize for the inconvenience and thank you for your patience and continued support. Please rest assured that system reliability is a top priority at Google, and we are making continuous improvements to make our systems better. We will conduct an internal investigation of this issue and make appropriate improvements to our systems to prevent or minimize future recurrence. We will provide a more detailed analysis of this incident to the affected customers once we have completed our internal investigation.
UPDATE 14:50CST: Gmail service has already been restored for some users, and we expect a resolution for all users in the near future. Please note this time frame is an estimate and may change. Delivery of messages sent to affected users during the issue may be delayed.
UPDATE 11:51CST: Gmail service has already been restored for some users, and we expect a resolution for all users in the near future. Please note this time frame is an estimate and may change.
We’re investigating reports of an issue with Gmail. We will provide more information shortly. Based on reports, it affects only Google for Work Gmail users. The users are redirected to a page with ‘Service not available, contact your administrator’. Workaround: Disable Gmail Service in Admin Console UI, save the changes, enable it back, save the changes.