Restrict Standard User from not removing the COM-Addins registered under HKLM with Admin rights.

Question

Hello,
I have developed a COM-Addin for word 2013 by VS 2013 and installed it under the HKLM with Admin rights. Now from an non-admin account, ie Standard User I'm able to uncheck that addin from the COM-Addins dialog and remove it also. Previously I have done the
same thing for word 2007 addins and if a non-admin user tries to uncheck it the warning "The
connected state of Office Add-ins registered in HKEY_LOCAL_MACHINE cannot be changed" pops
up. But this is not happening for office 2013 apps(basically word, excel and powerpoint). 
This is happening for all Add-Ins installed under HKLM.
How can a Standard User be restricted from unchecking and removing the Office Addins registered under HKEY_LOCAL_MACHINE with same warning "The
connected state of Office Add-ins registered in HKEY_LOCAL_MACHINE cannot be changed" in
a pop-up box?
Regards, Sayan

Answer 1

Hi,
The behavior is changed since Office 2010. Office 2010 and Office 2013 allows a standard user to turn a per-machine add-in off by unchecking the add-in in the COM Add-ins dialog.
To restrict Standard User from not removing the COM Add-ins, we can try to add the add-in to
the Group Policy option: List of managed add-ins in the Office Group Policy template.
Word for example, the policy is under:
User Configuration\Administrative Templates\Microsoft Word 2013\Miscellaneous
To enable this policy setting, provide the following information for each add-in:
In "Value name", specify the programmatic identifier (ProgID) for COM add-ins, or specify the file name of Word add-ins.
To obtain the ProgID for an add-in, use Registry Editor on the client computer where the add-in is installed to locate key names under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\Word\Addins.
To obtain the file name of an add-in, click the File menu in the application where the add-in is installed. Click Options, click Add-ins, and then use the Location column to determine the file name of the add-in.
In "Value," specify the value as follows:
To specify that an add-in is always enabled, type 1.
Hope this helps.
Regards,
Steve Fan
TechNet Community Support