For my system, in X2, it shows up in the Plugin Manager, under VST Audio Effects (VST), as VC-64, and in its Properties, its path and name are:
"c:\program files\cakewalk\vstplugins\VintageChannel\Vintage_Channel_VC64.dl"
Everything looks the same for it in the X3 Plugin Manager, as well.
Perhaps you could check the above location, and make sure it really is there, and you could also check to see if it was, for some reason, excluded.
Bob Bone