Se você instalou a grande Atualização KB2919355, instale a seguinte Atualização para corrigir o problema:
Você não consegue desinstalar o IIS depois de instalar o KB2919355 no Windows 8.1 ou no Windows Server 2012 R2
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Consider the following scenario:
You have a computer that is running Windows 8.1 or Windows Server 2012 R2.
You have update 2919355 and Microsoft Internet Information Services (IIS) installed on the computer.
You try to uninstall IIS.In this scenario, the uninstallation fails. Additionally, IIS is rolled back and may not function correctly.
To resolve this issue, install the update that is described in this article before uninstalling IIS.
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