admin receives their invite, they can then choose to share it internally in their organization with other testers. Interested testers can visit to sign up for an invite. The company says the Preview build will be released in three stages, starting with today’s launch, before the public version is made available. admins before becoming more broadly available. However, Microsoft says invites will roll out first to I.T. administrators and individuals can sign up to test the new desktop software, which introduces features like Outlook integration, additional security, and calls that allow for up to 250 people versus Skype’s 25 max. Microsoft announced this morning the launch of Skype for Business for Mac Preview – the business-focused version of Skype’s communications services aimed at a commercial client base.