Starting with Windows 10, version 1607 (Windows 10 Anniversary Update), you can move from Windows 10 Pro to Windows 10 Enterprise more easily than ever before—no keys and no reboots. To get started, there are two options for you to start the subscription, either to get Windows 10 E3 or go for Windows 10 E5.
Whatever is the case, the steps to get started are the same. Below, are the steps that you can follow to start using Windows 10 as a Service once you buy a license.
1: First you need to install Windows 10 Pro in your device. Then you should visit the admin portal via http://portal.office.com and click billing section.
2: In the licenses tab, you can assign a Windows 10 Enterprise E3 license assuming that you have bought a E3 license.
3: Next, add the Windows 10 Enterprise E3 license to the Azure AD user to whom you plan to assign the license to and click save.
4: Now, in the PC settings of your PC (Assuming that you are assigning a license to your PC) , sign in with your user credential to join Azure AD as per below:
5: After you login for the first time, the OS- Windows 10 Pro will start the SKU transformation – and after a restart, Windows 10 Enterprise subscription will run in your system and you are ready to go.
Note that only PCs running Windows 10 Pro, version 1607 can get Windows 10 Enterprise E3. After one of your users enters the Azure AD credentials associated with a Windows 10 Enterprise E3 license, the operating system turns from Windows 10 Pro to Windows 10 Enterprise and all the appropriate Windows 10 Enterprise features are unlocked.
Even small- and medium-sized organizations can more easily take advantage of Windows 10 Enterprise features.
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