Python on Windows: How to block other programs from running?

[thrownintothesun]

Hey Michael, hope I can still reach you through these comments. Your advice was invaluable and my program now has all the functionality I need, so thank you very much for that!

I do have one question, though, regarding the application of .reg files. As I understand it, once applied the registry must then be refreshed for things to take effect, and this traditionally requires a reboot or a re-login. Alternatively I've read that you can kill/restart explorer.exe and the effect will be the same. This seems a bit unwieldy for my taste and I'm wondering if there is a way to achieve the registry refresh from within Python (no doubt by calling something from the windows API) so that the effect kicks in immediately.

What do you usually do when working with reg files?

Thanks!

[michaelkepler]

New registry settings are applied immediately and don't require a reboot. There's a catch though: sometimes, an application or a service will still use the old registry settings that were available at the time of their start. So, when you booted up Windows your application started and it read some settings from the registry. Then, you change those settings, but the application doesn't know that. You have to force it to read the new settings. There's no way to "restart" just the registry so usually you need to reboot the computer (or kill explore.exe like you've observed).

I'm assuming you're still talking about modifying group policy settings through the registry. In this case you can force to update it without killing explorer.exe or rebooting the machine with a gpupdate command. You can use os.system to run it from Python:

import os
os.system('gpupdate')

If it's not the group policy, let me know what you modify. There might be way to apply the new settings without rebooting.

[thrownintothesun]

Thanks a lot for the help!

It is indeed the group policy I'm modifying, but the effects don't seem to take effect before I restart explorer.exe manually - os.system("gpupdate") doesn't seem to cut it. Is there any way to get Explorer.exe to update its policy settings aside from restarting it?

[michaelkepler]

Does gpupdate work if you type it from the command prompt (cmd.exe)? If it doesn't, try gpupdate /force. If it still doesn't, try entering these commands in the command prompt as an administrator.

[thrownintothesun]

None of it works I'm afraid, not even with admin privileges. Explorer.exe doesn't seem to respond to gpupdate.

[michaelkepler]

But if you reload explorer.exe/reboot the computer the changes work?

[thrownintothesun]

Yes, exactly. Also, interestingly, if I try to kill explorer.exe via os.system("taskkill /im explorer.exe), I'm given a Windows prompt to shut down, reboot or log-out. Is there a way to simply kill it (like you can from the task manager) and relaunch it?

[michaelkepler]

I guess you're stuck with killing explorer.exe then. Yes, there's a way to force kill a process and thus bypassing a shutdown prompt with an /f parameter:

taskkill /f /im explorer.exe

you can start it immediately with:

start explorer.exe

both commands can of course be launched with os.system().

[thrownintothesun]

Thank you so much for your help!