Microsoft is letting consumers download Windows 10 Home or Pro for free on their older PCs, but the company is still charging for businesses to get Windows 10 Enterprise. However, they have the option of getting a 90-day free trial version of the OS.
The trial version is available to download via Microsoft's TechNet Evaluation Center. It states:
"We highly recommend that organizations make use of the Windows 10 Enterprise 90-day Evaluation to try out deployment and management scenarios, test compatibility with hardware and applications, and to get hands on experience with Windows 10 Enterprise features."
There's also a version of Windows 10 Enterprise that's free to download for Windows Insiders, but Microsoft says that version will expire on October 1, with reminders popping up on September 15. Microsoft says, "After October 1, a clean installation of Windows 10, the Windows 10 Enterprise 90-day Evaluation, or your former operating system will be required; and you will need to reinstall all of your programs and data."