py2exe fails to generate an executable

Question

I put this in all my setup.py scripts:

distutils.core.setup(
    options = {
        "py2exe": {
            "dll_excludes": ["MSVCP90.dll"]
        }
    },
    ...
)

This keeps py2exe quiet, but you still need to make sure that dll is on the user's machine.

I've discovered that py2exe works just fine if I comment out the part of my program that uses wxPython. Also, when I use py2exe on the 'simple' sample that comes with its download (i.e. in Python26\Lib\site-packages\py2exe\samples\simple), I get this error message:

*** finding dlls needed ***
error: MSVCP90.dll: No such file or directory

So something about wxPython makes py2exe think I need a Visual Studio 2008 DLL. I don't have VS2008, and yet my program works perfectly well as a directory of Python modules. I found a copy of MSVCP90.DLL on the web, installed it in Python26/DLLs, and py2exe now works fine.

I still don't understand where this dependency has come from, since I can run my code perfectly okay without py2exe. It's also annoying that py2exe didn't give me an error message like it did with the test_wx.py sample.

Further update: When I tried to run the output from py2exe on another PC, I discovered that it needed to have MSVCR90.DLL installed; so if your target PC hasn't got Visual C++ 2008 already installed, I recommend you download and install the Microsoft Visual C++ 2008 Redistributable Package.

wxPython has nothing to do with it. Before Python 2.6, Python used Visual Studio 2003 as their Windows compiler. Beginning with 2.6, they switched to Visual Studio 2008, which requires a manifest file in some situations. This has been well documented. See the following links:

http://wiki.wxpython.org/py2exe

http://py2exe.org/index.cgi/Tutorial#Step52

Also, if you're creating a wxPython application with py2exe, then you want to set the windows parameter, NOT the console one. Maybe my tutorial will help you:

http://www.blog.pythonlibrary.org/2010/07/31/a-py2exe-tutorial-build-a-binary-series/

It looks like this is only a dependency for Python 2.6. I wasn't getting this error under 2.5, but after the upgrade I am.

This email thread has some background for why the problem exists and how to fix it:
http://www.nabble.com/py2exe,-Py26,-wxPython-and-dll-td20556399.html

I didn't want to have to install the vcredist. My application currently requires no installation and can be run by non-administrators, which is behavior I don't want to lose. So I followed the suggestions in the links and got the necessary Microsoft.VC90.CRT.manifest and msvcr90.dll by installing Python "for this user only". I also needed msvcp90.dll that I found in the WinSxS folder of an "all users" Python 2.6 install. Since I already had two of the three, I included msvcm90.dll to prevent future errors though I didn't get any immediate errors when I left it out. I put the manifest and the three DLLs in the libs folder used by my frozen application.

The trick I had to perform was including an additional copy of the manifest and msvcr90.dll in the root of my application folder next to by py2exe generated executable. This copy of the DLL is used to bootstrap the application, but then it appears to only look in the libs folder.

Hopefully that discovery helps someone else out.

Also, I had the same problem with having py2exe log a real error message. Then I realized that stderr wasn't getting redirected into my log file. Add "> build.log 2>&1" on the command line where you invoke py2exe.

import sys

sys.path.append('C:\\WINDOWS\\WinSxS\\x86_microsoft.vc90.crt_1fc8b3b9a1e18e3b_9.0.30729.4148_none_5090ab56bcba71c2')

On each Windows, you can find the file MSVCP90.dll in some subdirectory in C:\\WINDOWS\\WinSxS\\

In my case, the directory was: x86_microsoft.vc90.crt_1fc8b3b9a1e18e3b_9.0.30729.4148_none_5090ab56bcba71c2.

Go to C:\\WINDOWS\\WinSxS\\ and use windows file search to find MSVCP90.dll.