Microsoft has finally fixed an Exchange Online outage that left affected users without access to email for almost nine hours on Tuesday, prompting many to vent their frustration online as they struggled to get their work done.
The company hasn't said how many customers were impacted, but judging by the volume of complaints posted in discussion forums and social media sites, it must have hit a substantial number of users.
Plus, the length of the outage, and the fact that it struck during U.S. work hours, makes it a significant and embarrassing one for Microsoft, which is locked in a fight with Google in the cloud communication and collaboration software market.
Exchange Online is sold as a standalone service, and also as a component of Office 365, Microsoft's cloud communication and collaboration suite for businesses, schools, government agencies and nonprofit organizations.
In an update posted in page 15 of a discussion thread in the Office 365 support forum, a Microsoft representative declared that the service had been restored around 6 p.m. U.S. Eastern Time. The outage hit shortly after 9 a.m.
"Investigation determined that a portion of the networking infrastructure entered into a degraded state. Engineers made configuration changes on the affected capacity to remediate end-user impact," wrote the Microsoft support official, identified as David Zhang.
A common theme among affected users who complained online was that Microsoft was slow to acknowledge the outage and didn't communicate well with customers. Many felt that the Office 365 status dashboard wasn't updated quickly enough to reflect the problem.
A good sample of these complaints is encapsulated in the reactions to this update Microsoft posted to the Office 365 Twitter account at one point during the afternoon.
Outages such as this one create difficult situations for IT departments whose companies have shut down their on-premises servers and switched to vendor-hosted cloud services like Office 365. In these situations, IT pros have little to no control over the outage and yet have to field queries and complaints from their angry users.
Inevitably, these types of outages also trigger second-guessing of the decision to move to cloud services and give up the inherent control of running one's own servers for email and other applications. This second-guessing is usually directed at the high-level IT executive who pushed for the move to the cloud, like CIOs, CTOs and IT managers.
Office 365 comes in a variety of editions that vary in price and in the applications and tools they include. Most Office 365 editions come with Exchange Online, SharePoint Online, Lync Online and OneDrive for Business, and some also include the full-featured Office productivity app suite.
The basic version of Office 365 for Education, called A2, is free, while the most sophisticated version for businesses, Office 365 Enterprise E4, costs US$22 per user, per month and includes a 99.9 percent uptime guarantee.
A Microsoft spokeswoman contacted via email acknowledged the problem, but didn't provide details about the number of customers affected.
Juan Carlos Perez covers enterprise communication/collaboration suites, operating systems, browsers and general technology breaking news for The IDG News Service. Follow Juan on Twitter at @JuanCPerezIDG.