Error installing CuPy in Windows even with wheels (pip install cupy-cuda91)

I have been trying to install CuPy in my Windows 10 64bits machine, to use with Python 2.7 and Cuda 9.1.85:

>nvcc --version nvcc: NVIDIA (R) Cuda compiler driver Copyright (c) 2005-2017 NVIDIA Corporation Built on Fri_Nov__3_21:08:12_Central_Daylight_Time_2017 Cuda compilation tools, release 9.1, V9.1.85

My GPU also meets the requirements, since it is a GeForce GTX 960M thus with 5.0 compute capability.

When I try pip install cupy I get a few errors in the installation log (which you can find attached). Then when I try pip install cupy-cuda91 I get:

>pip install cupy-cuda91 Collecting cupy-cuda91 Could not find a version that satisfies the requirement cupy-cuda91 (from versions: ) No matching distribution found for cupy-cuda91

I wonder if I am missing any basic step here, or whether you can help me sort out what might be interfering with the installation since I seem to have all requirements met to easily install via wheels.

cuda_install_log.txt

[disktnk]

On Windows OS, cupy wheel only supports Python3.6. ref: https://pypi.org/project/cupy-cuda91/5.0.0b3/#files

Python2.7 (compiling) requires Visual Studio9.0 (VS2008) but CUDA support from Visual Studio 2012~, so local build may also be difficult, I think.

[vasselai]

@kmaehashi I solved the issue and, to help others that might be in the same situation in the future, here’s the solution: for some reason, pip and pip3 were being unable to call Visual Studio C++ command line compiler. Reinstalling Microsoft Visual C++ Build Tools 2017 did the trick.

While all my code is done with Python 2.7, now I have CuPY properly running with Python 3.6 in a separate Anaconda environment for some testing.

Consider my case closed 😃