Windows 10 Isn't Entirely Free for Everyone

— -- Not everyone will be getting a free upgrade to Windows 10 when the operating system update is released sometime later this year.

Microsoft users were treated to a spot of good news last month when the company revealed the update will be free for users who have Windows 8.1, Windows 7 and Windows Phone 8.1. However, in a blog post, the company explained that the giveaway isn't for everyone.

Windows 7 Enterprise and Windows 8/8.1 Enterprise will not be eligible for the free upgrade, according to Microsoft. The enterprise versions of the software are designed for organizations rather than individual users.

"Active Software Assurance customers will continue to have rights to upgrade to Windows 10 enterprise offerings outside of this offer -- while also benefiting from the full flexibility to deploy Windows 10 using their existing management infrastructure," the company said.

The free upgrade will still extend to "hundreds of millions of customers" around the world, according to Microsoft.

It's the first time the company has offered a free upgrade on this scale. Getting so many people on board with the Windows refresh will "create a broad opportunity for our ecosystem partners to drive innovation, and deliver value to all Windows 10 customers," the company said.

The world met Windows 10 at an event last year. However, last month Microsoft showed off new consumer-driven features that support the company's goal to increase productivity.