Block ActiveX Controls in Internet Explorer

Internet Explorer's full spectrum of functionality depends on the many useful ActiveX controls available on the internet. However, most spyware installs itself using an ActiveX plug-in when a browser window is opened. Hence, disabling ActiveX controls entirely is not a good solution.

Solution:

You can stop certain ActiveX controls from activating via the kill bit registry key as described in Microsoft Knowledge Base article 240797

This is one method to avoid spyware.

The "kill bit" is a flag in the Class Identifier, or CLSID, for the ActiveX control.

The CLSID for any given ActiveX component is found in the Registry:
HKEY_CLASSES_ROOT\CLSID.

Internet Explorer maintains a separate list of compatible ActiveX controls in:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\ActiveX Compatibility.

To stop a particular control from loading:

• Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\ActiveX Compatibility

• Add a new subkey with the name of the CLSID for an ActiveX control

• Under this new subkey add a DWORD value named "Compatibility Flags"

• Set the value of "Compatibility Flags" to 400 hex

CLSIDs are globally unique so once a control is blocked in this fashion it is blocked permanently (unless it is reissued with a new CLSID).

Spywareguide.com maintains a REG file that has hundreds of ActiveX controls known to be spyware.

Eric L. Howes creator of IE-SPYAD maintains batch files which can install activeX blocking via batch files.