You may upgrade to Windows 8.1 through Windows Update or the Windows Store, or download Windows 8.1 Update Package KB2871839. But when checking your system doesn’t change to Windows 8.1, I have to tell you that you cannot upgrade to Windows 8.1 right now.

According to Microsoft, there are 4 reasons why you cannot upgrade to Windows 8.1, at least right now:

1. Your PC was not installed the update KB2871389

2. You are using Windows 8 Enterprise

3. You are using Windows 8 Pro is activated by using KMS method

4. You are using the Windows 8 ISO installed file provided by MSDN and is active with the MAK key (multiple activation keys).