error: Unable to find vcvarsall.bat

Update: Comments point out that the instructions here may be dangerous. Consider using the Visual C++ 2008 Express edition or the purpose-built Microsoft Visual C++ Compiler for Python (details) and NOT using the original answer below. Original error message means the required version of Visual C++ is not installed. For Windows installations: While running setup.py for package installations, Python 2.7 searches for an installed Visual Studio 2008. You can trick Python to use a newer Visual Studio by setting the correct path in VS90COMNTOOLS environment variable before calling setup.py. Execute the following command based on the version of Visual Studio installed: Visual Studio 2010 (VS10): SET VS90COMNTOOLS=%VS100COMNTOOLS% Visual Studio 2012 (VS11): SET VS90COMNTOOLS=%VS110COMNTOOLS% Visual Studio 2013 (VS12): SET VS90COMNTOOLS=%VS120COMNTOOLS% Visual Studio 2015 (VS14): SET VS90COMNTOOLS=%VS140COMNTOOLS% WARNING: As noted below, this answer is unlikely to work if you are trying to compile python modules. See Building lxml for Python 2.7 on Windows for details.