cx_Oracle throws: ImportError: DLL load failed: This application has failed to start ...

[Albert-Jan Roskam]

--------------------------------------------
On Sun, 11/24/13, MRAB <python at mrabarnett.plus.com> wrote:

 Subject: Re: cx_Oracle throws: ImportError: DLL load failed: This application has failed to start ...
 To: python-list at python.org
 Date: Sunday, November 24, 2013, 7:17 PM
 
 On 24/11/2013 17:12, Ruben van den
 Berg wrote:
 > I'm on Windows XP SP3, Python 2.7.1. On running
 >
 > import cx_Oracle
 >
 > I got the error
 >
 > ImportError: DLL load failed: This application has
 failed to start because the application configuration is
 incorrect. Reinstalling the application may fix this
 problem.
 >
 > I then ran Dependency Walker on cx_Oracle.pyd. Its
 first complaint was about msvcr80.dll. However, this file is
 present in
 C:\WINDOWS\WinSxS\x86_Microsoft.VC80.CRT_1fc8b3b9a1e18e3b_8.0.50727.91_x-ww_0de56c07.
 (I believe it's part of the MS Visual Studio C++ 2008
 package which I installed.)
 >
 > I obviously uninstalled and reinstalled the cx_Oracle a
 couple of times but so far to no avail.
 >
 > Does anybody have a clue what to try next?
 >
 > For a screenshot of Dependency Walker, please see: https://dl.dropboxusercontent.com/u/116120595/dep_walker_orac.jpg
 >
 It looks like it's a path issue.
 
 You say that msvcr80.dll is in 
 C:\WINDOWS\WinSxS\x86_Microsoft.VC80.CRT_1fc8b3b9a1e18e3b_8.0.50727.91_x-ww_0de56c07,
 
 but is that folder listed as part of the search path?
 
 Have a look at the Windows' PATH environment variable.


===> Unlike in Linux with LD_LIBRARY_PATH, you can change PATH at runtime in Windows, e.g
import os, sys, ctypes
if sys.platform.startswith("win"):
    os.environ["PATH"] += (os.pathsep + r"c:\your\new\path")
    ctypes.WinDLL("msvcr80.dll")