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To find your plug-in: Use a program to look for it.
You might install "EasyFind" if you do not have it.
You can download a free trial from here:
CalcService and EasyFind Download: http://www.devontechnologies.com/download/products.html
The search for the plug-in with EasyFind:
On my machine I found it in exact the location that Tony has shown in his screenshot.
I think if you do not find the plug-in in its proper place, then the installion did not install it.