I'm running a protocol that's been in production for over a year.  It is called by another program that passes info so that it can fetch a 3D structure from the database and pass it to the DS visualizer.  It works great.  But, we have a new employee that doesn't see the plug-in properly. 
So far we've done these things and I'd like some ideas about what else to check for.
1) yes, other people with the same windows version and same IE version can see it fine
2) reinstall java and activeX
3) yes, testing it on the tests at  file:///C:/Program%20Files%20(x86)/Accelrys/DS%20ActiveX%20Control%204.1/share/Samples/Samples.htm
works fine.
I'm not sure what to try next....