This is the way to prevent the automatically upgrade of Office 365 ProPlus 2013 to 2016

Solution 1: Change the Registry

Go to the following location in the registry on each affected computer:

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\office\15.0\common\officeupdate

Add the following value under the office update subkey:

“enableautomaticupgrade“=dword:00000000

Solution 2: GPO

Add

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