Error: Microsoft Visual C++ 10.0 is required (Unable to find vcvarsall.bat) when running Python script [duplicate]

Question

Im trying to install numpy with PyCharm but i keep getting this error:

error: Microsoft Visual C++ 10.0 is required (Unable to find vcvarsall.bat).

Can someone please explain to me exactly what i have to do to fix this error(and as simple and detailed as possible)? im using python 3.4.2 (i know this has been answered before but i did not understand it).

Answer 1

I was able to fix this on Windows 7 64-bit running Python 3.4.3 by running the set command at a command prompt to determine the existing Visual Studio tools environment variable; in my case it was VS140COMNTOOLS for Visual Studio Community 2015.

Then run the following (substituting the variable on the right-hand side if yours has a different name):

set VS100COMNTOOLS=%VS140COMNTOOLS% 

This allowed me to install the PyCrypto module that was previously giving me the same error as the OP.

For a more permanent solution, add this environment variable to your Windows environment via Control Panel ("Edit the system environment variables"), though you might need to use the actual path instead of the variable substitution.

Answer 2

Python 3.3 and later now uses the 2010 compiler. To best way to solve the issue is to just install Visual C++ Express 2010 for free.

Now comes the harder part for 64 bit users and to be honest I just moved to 32 bit but 2010 express doesn't come with a 64 bit compiler (you get a new error, ValueError: ['path'] ) so you have to install Microsoft SDK 7.1 and follow the directions here to get the 64 bit compiler working with python: Python PIP has issues with path for MS Visual Studio 2010 Express for 64-bit install on Windows 7

It may just be easier for you to use the 32 bit version for now. In addition to getting the compiler working, you can bypass the need to compile many modules by getting the binary wheel file from this locaiton http://www.lfd.uci.edu/~gohlke/pythonlibs/

Just download the .whl file you need, shift + right click the download folder and select "open command window here" and run

pip install module-name.whl  

I used that method on 64 bit 3.4.3 before I broke down and decided to just get a working compiler for pip compiles modules from source by default, which is why the binary wheel files work and having pip build from source doesn't.

People getting this (vcvarsall.bat) error on Python 2.7 can instead install "Microsoft Visual C++ Compiler for Python 2.7"