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Installation Problems

Check for duplicate Python system files

Check for multiple versions of pythonxx.dll, pywintypesxx.dll, or pythoncomxx.dll, where xx is the Python version (eg, 23).  In general, you should find exactly one copy of these files in your Windows system directory (generally named SYSTEM32.)  However, non admin installs will place then in your main Python directory.  Check for copies of these files in both places - if you find multiple copies, delete all but the ones in your system directory.

COM related errors

Occasionally you may see installation errors related to regisering COM objects.  The installation will still succeed, but you may have trouble using the parts of thexe extensions relating to COM.  Common causes for this are discussed here

Note: If your installation generated COM related errors and you need to install a COM update, it is recommended you uninstall the installation, perform the update COM, then re-install the extensions

Windows XP and later

There should be no errors relating to Windows XP - please report a bug via the sourceforge pages if you see any problems.

Windows 2000/9x

Windows 2000 or 9x which still have old Internet Explorer versions, specifically version 4.01, may experience an error registring Python COM objects.  The error will usually include the error:

  pywintypes.com_error: (-2147467262, 'No such interface supported', None, None)
It appears this version of IE shipped with an incorrect comcat.dll (which resides in the system32 directory.) You should upgrade your IE version to solve this.

Windows 9x

If you are using Windows 9x, have not updated Internet Explorer or installed MSOffice or any other large, popular application, you may need to update the COM version on your system.  Lots of commonly used software will update these automatically for your (such as Internet Explorer, or Microsoft Office), so many old systems are likely to be fine - but if you do experience issues relating to COM, you should install an update
The simplest way to get up-to-date COM DLLs is to install the latest DCOM updates. Visit the DCOM download pages at, select Resources->Downloads, and grab the DCOM update for your system.

A small number of users have reported old DLLs that refuse to go away even after updating their system. Although very rare, if all else fails, the key system DLLs appear to be ole32.dll and oleaut32.dll

The versions I have on my Windows NT 4 SP3 machine are:

  • ole32.dll - 4.00
  • oleaut32.dll - 2.30.4265

My Windows 98 box has:

  • ole32.dll -
  • oleaut32.dll - 2.30.4261

If your version of these files are significantly out of date, then that is likely to be your problem.  (See Finding a version of a DLL for more information)

Finding a version of a DLL

To find the "version of a DLL", follow this process:

  • Using Windows Explorer, locate the DLL in question (usually in the Windows System directory)
  • Display the properties for the file. This can be done by right-clicking on the file, and selecting Properties from the menu.
  • On the properties dialog that is shown, click on the Version tab near the top of the form.

The version number should be displayed.

If you can not locate the file specified, it may be necessary to change the options for Windows explorer. If you select the View menu, then select Options (or Folder Options), there will be an option to hide system files - disable this option. Unfortunately, the exact process is different for Windows 95, 98 and NT

Check the correct Python DLLs have been installed

Note: This process currently does not work - the new build process does not tag the DLLs.
This normally happens when an old version of the extensions has been installed on the PC. You should check the version numbers of the files Pythoncom1x.dll and PyWinTypes1x.dll. Both these files are in your Windows system directory. (Click here for info on how to find a DLLs version)

The version numbers should be (or, where xxx is the build number of win32all you installed. For example, win32all-125.exe will install these DLLs with version; build 136 is likely to be (by the time we release 136 we will almost certainly be on 1.6 only :-) 

If old versions are installed, you should:

  • Uninstall the extensions using Control Panel/Add Remove Programs.
  • Delete these DLLs from your Windows System directory.
  • Reinstall the extensions.

If you are brave: The WinZip program can open the win32all-xxx.exe file, and display and extract the contents. If you are confident that you know all the files that were not installed correctly, you can extract and update the files manually.

[Wed Jul 27 08:02:53 2005 GMT+10]