Thank you for the detailed info. HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Python.File\shell only had "Edit with Pythonwin", and didn't have an "open" key. I added that in, along with one for the Python.NoConFile which was also missing "open", and it seems to be working happily now.
Again, many thanks for the replies. -----Original Message----- From: Python-list [mailto:python-list-bounces+david.raymond=tomtom....@python.org] On Behalf Of eryk sun Sent: Friday, November 09, 2018 6:43 PM To: Python Subject: Re: Windows file associations fix On 11/9/18, David Raymond <david.raym...@tomtom.com> wrote: > > And why does the Python installer have a check box for "Associate files with > Python" if it then promptly proceeds to destroy all those associations? > Could we maybe get that part of the installer fixed for future versions? The installer configures the HKCR setting to associate .py[w] files; however, it doesn't delete a user-choice setting in the shell. You should be able to restore the user choice to the launcher via the open-with -> choose another app dialog. Select the Python icon with a rocket on it (for py.exe; the python.exe icon has no rocket), enable the option to always use this application, and click ok. If that doesn't restore the association, you'll have to manually inspect and modify the settings. The following lists the shell's cached association for the .py file extension, including the user choice, if any: set "winkey=HKCU\Software\Microsoft\Windows\CurrentVersion" reg query %winkey%\Explorer\FileExts\.py /s Output: HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\ Explorer\FileExts\.py\OpenWithList a REG_SZ py.exe MRUList REG_SZ a HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\ Explorer\FileExts\.py\OpenWithProgids Python.File REG_NONE HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\ Explorer\FileExts\.py\UserChoice Hash REG_SZ aA7ZxnDmUdM= ProgId REG_SZ Python.File Currently I have a UserChoice setting locked in. The permissions and hash value prevent us from modifying this key, but we can delete it, in which case the shell reverts to using the cached OpenWith* associations. Here's a command to delete this key (or use regedit if you prefer a GUI), where %winkey% was previously defined above: reg delete %winkey%\Explorer\FileExts\.py\UserChoice If we instead delete the FileExts\.py key, the shell recomputes the association from the underlying HKCR settings, where HKCR is a merged view of [HKLM | HKCU]\Software\Classes. If that doesn't solve the problem, check the default value of [HKCU | HKLM]\Software\Classes\.py, and its OpenWithProgIds subkey if defined. Python's installer associates .py files with the "Python.File" program identifier (progid). If that's set correctly, check [HKCU | HKLM]\Software\Classes\Python.File to ensure it's set up to use the py.exe launcher. For example, the following displays the default "open" command for the local-machine Python.File progid: reg query HKLM\Software\Classes\Python.File\shell\open\command Output: HKEY_LOCAL_MACHINE\Software\Classes\Python.File\shell\open\command (Default) REG_SZ "C:\Windows\py.exe" "%1" %* "%1" (or sometimes "%L") is the fully-qualified path of the target .py script, and %* has the command-line arguments, if any. As a side note, you've probably seen examples that use CMD's assoc and ftype commands (from NT 4.0, circa 1996). These commands work with HKLM\Software\Classes, which is fine for classic file associations configured for all users. However, they do not show or modify HKCU settings, and they're unaware of updates to how the shell works since XP/Vista such as HKCR\Applications, HKCR\SystemFileAssociations, and application capability file associations linked in [HKCU | HKLM]\Software\RegisteredApplications. > Currently: Windows 7. Attempting to run a .py file opens up the "Open with" > dialog with a bunch of other programs listed. Clicking browse to manually > select the new python.exe doesn't add it to the list and won't let me do the > association. You shouldn't manually associate .py files by browsing for py.exe or python.exe. If you do this, the system creates an automatic progid that only includes the "%1" target, without the %* command-line arguments. Typically this broken progid will be "HKCU\Software\Classes\Applications\py.exe", or "HKCU\Software\Classes\Applications\python.exe", or "HKCU\Software\Classes\py_auto_file". Delete these keys if they exist. -- https://mail.python.org/mailman/listinfo/python-list -- https://mail.python.org/mailman/listinfo/python-list
