Installed plug-in not showing up

I've got a 6 user system that relies pretty heavily on the EventScript
plug in. I've copied the plug in to the /Program Files/FileMaker/
Extensions directory on all of the end-users computers. Everything is
working fine except for one computer, which doesn't list the plug in
under Edit->Preferences->Plug-Ins.

I am completely at a loss as to why this may be. I've uninstalled and
reinstalled the client and the plug-in several times. Any help would
be greatly appreciated.

Thank you,
Nate

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