Intermedia, one of the largest cloud service providers, is back online after suffering widespread service disruptions yesterday that denied subscribers access to email, cloud file systems and phone service. While the outage was disruptive, the real damage may be in Intermedia’s communications to partners and customers.

While Intermedia was struggling to bring services back online, partners and customers were left in the dark over what was happening, why they couldn’t access critical services and when to expect restoration.

Services are now stable, but Intermedia says it is continuing to investigate the root cause of the outage. This is the second time in two weeks Intermedia has had service disruptions due to routing table problems.

Intermedia is ensuring partners and customers that no data was lost or corrupted, no security breaches were detected and all email messages will be delivered as the backlog clears.

“On behalf of all of us at Intermedia, I offer a profound apology. We understand how essential our services are to your business. We fully appreciate the breadth of our responsibility. We live and breathe it every day,” wrote Intermedia CEO Phil Koen in a blog post.

Intermedia manages more than 500,000 Exchange mailboxes, making it one of the largest Microsoft service providers. The service problems prevented subscribers from accessing email, signing on to Microsoft Lync instant messenger, accessing and synchronizing files via the new SecuriSync service, and immobilized VoIP phone service and conference call lines.

Solution providers and customers are accustom to periodic service disruptions. However, the Intermedia’s lack of communications on what was happening tweaked users. The social universe exploded with complaints, as users took to Twitter to vent their frustrations over the lack of information. Solution providers tell Channelnomics that their account managers and contacts weren’t responding to voice messages. And Intermedia’s own Web site was dark for much of the day and, when accessible, provided few updates.

Intermedia says it tried to notify partners and customers of what was happening, but acknowledges that messages didn’t reach all and pledged to improve its communications systems.

“We will also improve the responsiveness and robustness of our customer notification tools and systems. Although we were successful in notifying many of our customers about the issues via alternate email addresses, text messages and HostPilot, not all customers were reached. Going forward, we will make more timely use of our website and social media—especially Twitter and Facebook,” Koen wrote.

The takeaway from Intermedia’s outage: Customers will tolerate service disruptions (to a degree) so long as they’re informed. Left to their own devices without information, they will spread doubt and dissatisfaction that could have lasting consequences.