Hi, That's a call for testing for 64 bits windows users out there: please try the following binary with the test suite: http://www.ar.media.kyoto-u.ac.jp/members/david/archives/numpy/numpy-1.3.0.d... python -c "import numpy; numpy.test()" Report any crash. I am particularly interested in vista and higher versions without visual studio installed - it looks like those cause a lot of trouble wrt the C runtime. *THIS IS ONLY FOR TESTING* - it is still far from being stable. Details: This one is built with free compilers (gcc + gfortran 4.4), and BLAS/LAPACK built with gfortran. This should enable openmp usage too (4.4 supports openmp3.0). It also means supporting scipy is not too far away - there are still some issues with C++, but hopefully, those are compiler bugs, and all numpy issues will have been sorted out. cheers, David