This is the kind of thing you can expect when you don't install to the default C: drive.
Best advice...don't do that. Get a larger C: drive if you need to.
You can try forcing the plug-in installers to install to this location:
E:\Program Files\Adobe\Adobe Premiere Pro CS6\Plug-ins\en_US
Just how large is your SSD drive?
I don't use SSD, but my boot drive has Win7 64bit Pro + CS5 Master Collection + MS Office Pro + a couple dozen or so small program + the usual My Documents folder... and I only use about 60 Gig of space
I DO have my Windows swap/page file directed to another drive, and I also DO have my cache files directed to another drive... read http://forums.adobe.com/thread/1007934?tstart=0
If you need to know how to redirect your Windows page/swap file, search at http://search.microsoft.com/search.aspx?mkt=en-US&setlang=en-US
Premiere Pro (and, I think, Encore) seem to have some locations hardwired into the program, so it is simply better to install to the C drive
Jim, if adobe required that the C drive always be used to install their software, they should put it on the requirements. Otherwise, I expect it to work properly or their SDK should also state that plug-ins must always be in the OS drive. Why is it too much to expect the program to look for plug-ins under the same drive as it lets you install the program to?
Buying new hardware is not necessary or helpful as I have already stated I found a workaround. I posted this information in case anyone else needs to know what to do.
The other two suggestions also provide some additional options for others with the same issue.
I have an 80GB SSD. I still have all of my CS5 programs installed there. Honestly, I am not sure that I will end up continuing with CS6 as it really does not provide me with any additional features that I have found myself taking advantage of so far. This and the fact that my plug-in's were not working, have kept me using CS5 programs mostly to date.
I do have my scratch disk elsewhere. I have tried to have other extra content files loaded elsewhere as well. But so far, I have not been able to use the goodies under programs like Encore either. so perhaps these might need to end up going to the C drive after I get to the bottom of that problem.