I've been trying to install numpy(http://numpy.scipy.org/) on my vista computer with no success. Every time I try I get a dialog box saying numpy-1.2.1-sse3.exe has stopped working. My instincts lead me to run spybot and a scan with AVG, I found that I had actually forgotten a couple things when I first set up both programs and I found a few things the programs suggested I remove but even after that I still get nowhere. I've also had a similar problem compiling mex files in matlab(the microsoft c/c++ compiler stops working) so I figured it might be windows related.
The spyware and virus scan was all I could think of doing, is there anything else I can do?