FCP X Plug-Ins

Where are the plug-ins for FCP X located?

I've located a few plug-in folders and I'm not sure which is the one I need. I would like to trash the plug-in that captures an MXF file from a Canon XF105 camera and re-install it. I don't understand why, with two identical machines, one machine is able to capture the footage while the second machine can not. Both machines have the same OS, same RAM, same FCPX version and same plug-in version.

-- Jeff