NIOS II EDS Installation on Windows8 fails (no SOPC builder shell)

When attempting to install NIOS II EDS, install file: 91_nios2eds_windows.exe, I get the following error:

"You need an installation of QuartusII / SOPC Builder 9.1 or later to install this kit (you have no SOPC Builder shell at C:\altera\14.0\quartus; check QUARTUS_ROOTDIR environment variable)."

I have already installed QuartusII. The directory c:\altera\14.0\quartus exists. An ls of the directory shows the sopc_builder directory exists:

% ls c:/altera/14.0/quartus/

bin32/ cusp/ dspba/ libraries/ readme.txt

bin64/ drivers/ eda/ lmf/ sopc_builder/

common/ dsp_builder/ extlibs32/ qdesigns/ version.txt

Is there something I can try to decipher why SOPC builder shell isn't found?

thanks

steve.