Attempting on windows the non-cygwin way


I am developing a GUI using PyQt, and my analysis is based on ROOT and python tools. Everything on a windows 32 bit machine (sigh…).

This is what I have installed:

  • python 2.6.6, installed with .msi file for x86 machine
  • Qt 4.7.4
  • PyQt 4.8.5, installed with .exe for python v2.6, x86

Now, I would like to take full advantage of the ROOT Qt-layer, and installed the binaries with the Qt-layer activated, ROOT v5.24, available at (I am unable to build ROOT from source following the non-cygwin approach.)

Trying to run example $ROOTSYS/tutorials/pyroot/, I got an error:

Traceback (most recent call last):
File “”, line 6, in
import ROOT
ImportError: No module named ROOT

Unexpected, given my environment variables setting:

PATH --> C:\Python26;C:\vim73;C:\BNL\ROOT\bin;C:\QtSDK\Desktop\Qt\4.7.4\msvc2008\bin;%PATH%
PYTHONPATH --> C:\BNL\ROOT\bin;C:\BNL\ROOT\lib;C:\Python26;C:\Python26\Lib;C:\Python26\Lib\site-packages;%ROOTSYS%;%ROOTSYS%\bin;%ROOTSYS%\lib;%PYTHONPATH%

I would greatly appreciate any help.



but were those binaries build with python support? That is, can you check for in $ROOTSYS/bin (or $ROOTSYS/lib)?


Dear Wim,

Thank you very much for your reply. I could not locate, hence I suppose the BNL binaries were not built with python support.

I have tried a few things:

First, I added the arguments ‘–enable-qt’ and ‘–enable-python’ for Gordon Watts’ ROOT builder, naively thinking it would do the job. It did not.

Then, I followed the instructions on “1. Full (aka Long and slow) installation” at

Unfortunately, the process of building root using the script did not complete, giving me an error:

NMAKE : fatal error U1077: ‘“C:\Program Files\Microsoft Visual Studio 9.0\VC\bin\cl.EXE”’ : return code ‘0xe0000135’

I really tried to follow the instructions, namely leaving C:\cygwin\Cygwin.bat unchanged, and including the Visual Studio 2008 bin directory in the PATH.

Do you have a suggestion on how to proceed?


is there no more to the error message other than 'return code ‘0xe0000135’? (The images you appear to have tried to link reference your local C:-drive, so are not visible to the topic.)

How did you add the VS’08 envars? The instructions that I’ve been given are:"C:\Program Files\Microsoft Visual Studio .NET 2008\Common7\Tools\vsvars32.bat"

I’ve never been all that lucky with building on windows, but the main cause of problems used to be same-named executables mixed from cygwin (e.g. both VC and cygwin have a link.exe).