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The 24.9.1 Windows installer (x86 and x64) makes a call to the Python interpreter. The Python script called during installation patches the path in a few Python programs in GMSPython\Scripts. This call can go wrong and there are currently two know reasons for this.

1) The system environment contains the PYTHONHOME environment variable that points to an incompatible Python version. The installer finishes with a pop-up with “Python has stopped working”:

2) The Windows system is missing some DLLs for the Universal C Runtime. These runtime libraries have been distributed by Microsoft in October 2015 as part of a regular Windows Update KB2999226. You will see a pop-up like this:

If this message appears do not try to reinstall GAMS. Install the missing run time libraries. Goto “Windows Updates” via the control panel and look for an optional update KB2999226 and install (more information at No need to reboot.

Even though both errors looks serious they can be safely ignored. GAMS will work properly. If the runtime libraries aee missing one will not be able to work with embedded Python code unless the missing DLLs get installed. If one trys to execute GAMS examples containing embedded Python code without the Universal C Runtime installed the following error message is given:

*** Error at line 7: Error executing "embeddedCode" section: The specified module could not be found.
 (problem occurred when trying to load embpycclib)

The GAMS embedded Python code facility works with the Python 3.6.1 installation that is shipped with the GAMS distribution (unless the command line switch pySetup is set to 0) independent of the system environment variable PYTHONHOME and hence no further action is required. Only if you want to run the Python executable in GMSPython\python.exe you cannot point to a different Python installation via an environment variable PYTHONHOME and need to unset this variable (set PYTHONHOME=).

The only effect of the failed Python run during installation is the unchanged Python programs in GMSPython\Scripts (e.g. pip.exe). If you want to run these, you need to do this from the GMSPython\Scripts directory or run (after fixing the causes for (1) and/or (2)) the program ..\python once in the GMSPython\Scripts directory.

platform/crash_during_installation_of_24.9.1.txt · Last modified: 2017/09/04 19:47 by admin