If you have multiple versions of the Plug-in installed on your computer, there may be conflicts when using Internet Explorer, Microsoft’s Web browser. Internet Explorer searches for other installed Plug-Ins, so it will also run plug-ins that are installed in the Netscape Plugins folder.
Click the About button 
on the Plug-in View Ribbon to
see the path for the Plug-in DLL. If the path does not point to the
Internet Explorer folder, the DLL currently being used should be
removed. This will force Internet Explorer to use the Plug-in DLLs
installed in the Internet Explorer Plugins folder.
Note: Both Netscape Navigator and Netscape Communicator check only their own Plugins folder—they do not search for other installed plug-ins.
Internet Explorer handles support for Microsoft formats, such as Word and Excel. Microsoft does not provide a means to override this support.
If both Windows 95 and Windows NT are installed on the same computer, Internet Explorer may be installed in two different locations, one for 95 and one for NT. Ensure that the Plug-in DLLs are installed in the correct Internet Explorer’s Plugins folder. If not, copy them to the correct folder and restart Internet Explorer. For more information, see Ensure correct plug-in path.