How do I install PyCrypto on Windows?

Question

I've read every other google source and SO thread, with nothing working.

Python 2.7.3 32bit installed on Windows 7 64bit. Download, extracting, and then trying to install PyCrypto results in "Unable to find vcvarsall.bat".

So I install MinGW and tack that on the install line as the compiler of choice. But then I get the error "RuntimeError: chmod error".

How in the world do I get around this? I've tried using pip, which gives the same result. I found a prebuilt PyCrypto 2.3 binary and installed that, but it's nowhere to be found on the system (not working).

Any ideas?

Answer 1

If you don't already have a C/C++ development environment installed that is compatible with the Visual Studio binaries distributed by Python.org, then you should stick to installing only pure Python packages or packages for which a Windows binary is available.

Fortunately, there are PyCrypto binaries available for Windows: http://www.voidspace.org.uk/python/modules.shtml#pycrypto

UPDATE:
As @Udi suggests in the comment below, the following command also installs pycrypto and can be used in virtualenv as well:

easy_install http://www.voidspace.org.uk/python/pycrypto-2.6.1/pycrypto-2.6.1.win32-py2.7.exe 

Notice to choose the relevant link for your setup from this list

If you're looking for builds for Python 3.5, see PyCrypto on python 3.5

Answer 2

Microsoft has recently recently released a standalone, dedicated Microsoft Visual C++ Compiler for Python 2.7. If you're using Python 2.7, simply install that compiler and Setuptools 6.0 or later, and most packages with C extensions will now compile readily.