Microsoft Corp. is pushing hard to get more of its partners to sell and support its online productivity suite, Microsoft Office 365. Some solution providers remain reluctant amid questions about reliability. Microsoft is giving skeptics reason for pause by releasing its uptime stats that show the service has an average 99.97% availability rating for the last year.

In a blog post, Microsoft revealed that for the last four quarters, Office 365 has had virtually no downtime. From July 2012 to June 2013, the service’s quarterly uptime was 99.98 percent, 99.97 percent, 99.94 percent and 99.97 percent, for each respective quarter.

“We have been building enterprise-class solutions for decades. In addition, Microsoft runs a number of cloud services like Office 365, Windows Azure, CRM Online, Outlook.com, SkyDrive, Bing, Skype and Xbox Live to  name a few. We benefit from this diversity of services, leveraging best practices from each service across the others improving both the design of the software as well as operational processes,” wrote Rajesh Jha.

The Microsoft Office 365 availability rates are reflective of a number of hosted services, including Exchange, SharePoint, Lync and Office Web apps. They do not include consumer services; only business, education and government segments.

Microsoft’s stated goal is to provide uptime of 99.99 percent at any given time. The company cautions that individual user experiences may vary based on geographic location and conditions, such as local bandwidth provider outages, that may affect service.

Until now, Redmond has not made its Microsoft Office 365 uptime rates available. Going forward, the company says it will publish quarterly uptime numbers through the Office 365 Trust Center.

Microsoft is betting big on Office 365 for being a major tent pole in its cloud strategy. It’s incenting partners to sell Microsoft Office 365 to convert its legacy Office licensing business to an annuity cloud business. Additionally, it’s trying to staunch the momentum of Google and its Apps suite, which is racking up wins in small business, government and education.

Availability remains a major concern for cloud consumers. A service, especially one used as frequently as Office, is useless if you can’t reach it over the Internet. In 2011, Google published a study that stated the only company to achieve the fabled five-nines availability rate was AT&T with dial-tone service. At that rate, users only experienced 5.26 minutes of downtime. At four-nine availability, the annual downtime is 52.56 minutes.

While Microsoft Office 365 is proving a reasonable alternative to conventional software licenses, the company is having a hard time getting partners engaged. At the annual Worldwide Partner Conference in Houston last month, Microsoft officials said only 3 percent of its partners — roughly 21,000 — are currently selling cloud applications.

Regularly publishing availability rates may help build confidence in cloud services among Microsoft’s partners and customers. However, getting partners to engage in cloud sales requires more than just confidence. Microsoft still needs to work on compensation, channel conflict and value-add equations for partners to fully engage.