How to disable the “Test mode” message that is displayed in Windows..
You receive the following message in the lower-right corner of the desktop, depending on your version of Windows.
Windows 8.1 Enterprise
To fix this problem in Windows 8, follow below steps:
Open Command Prompt with Administrator permissions.
In the Command Prompt window, type the following command, and then press Enter.
bcdedit -set TESTSIGNING OFF
Now restart the Computer..