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Why am I getting "Importing the numpy C-extensions failed" on some systems, but not all systems running python script?

I built a python based program. Prior to this project, I have not run a python program from an exe, but I needed to run this project from an exe on a Windows 10 machine. Using pyinstaller I created and tested the final project without issue, but as soon as I set it up on another computer, it returned an "Importing the numpy C-extensions failed" error message. This seemed weird because I did not receive this error on my computer. So I created a clean installation on a VM, and no error. The other system has python installed, but the version is the same as the one I am using on my computer. Regardless of the installed python version, I thought pyinstaller created a stand-alone python environment.
Is there something I should check or compare between the two systems?
Additionally, my system and the VM started the program without a Windows Defender popup, but the problematic system shows a "Windows protected your PC" popup that needs to be bypassed. Is there a Windows defender setting that might be causing this issue?
Thank you to anyone who has information on this issue. I am fairly new to Python and could use any positive advice available.
I have run the program on a clean VM, with no issues. After some research, I tried uninstalling and reinstalling the numpy on the problematic system, but the issue persists. I cannot figure out what is casuing the error on one system but not any others.

0x80070643 error while installing Python 3.6

I'm actually using Python for an audio steganography project but I have some troubles.
I searched this error code on the forum, but I found things about SQL installations and not Python.
I'm trying to re-install Python 3.6.5 after an uninstall, because of a bug with pip.
I installed Python 2.7, Python 3.6.5, Python with VS 2017, before uninstall it because it wasn't working.
However, when I'm runing the installer as an administrator, hit "customize installation", tick everything excpet "balblalblabal (this requires VS 2015 or later)", and click on "install", it tells me that :
.
I realy need Python to work and I'm now stuck ...
If anybody here could help me, it would be nice !
Thanks all,
maleik.
PS : I have the log for you :*
The log link

I found this in the log file which you have attached. Try cleaning the registry with CC cleaner and give it a try. If it still doesn't work, try installing python with web installer Python Web Installed 3.6.5.
[3DA0:2968][2018-12-05T20:46:18]e000: Error 0x80070643: Failed to install MSI package.
[3DA0:2968][2018-12-05T20:46:18]e000: Error 0x80070643: Failed to execute MSI package.
[2610:03A4][2018-12-05T20:46:18]e000: Error 0x80070643: Failed to configure per-machine MSI package.
[2610:03A4][2018-12-05T20:46:18]i319: Applied execute package: core_AllUsers, result: 0x80070643, restart: None
[2610:03A4][2018-12-05T20:46:18]e000: Error 0x80070643: Failed to execute MSI package

I installed python from Microsoft store after facing this problem and it magically got installed without any error as it may have directly been installed. I don't know but try if it eorks for you too.

You need to run the installation as a local administrator.

I had the same problem installing Python version 3.9 for the first time on my Windows 10, as this same problem happens to many users trying to install Python, the best solution I accidentally, just like #MANAN AGGARWAL discovered trying to check if I already had a version of Python installed on my computer by the DOS Command Prompt, was:
Open the DOS Command Prompt (cmd) and dictate "python": if a screen shows you a version, it's clearly not the first time you've installed Python, so if you want to upgrade you should try: https: / /www.delftstack.com/en/howto/python/how-to-update-python/ But if you've never installed any version of Python, the solution lies in updating your operating system to the latest version through Windows Update, and open the command prompt and type Python, or go directly to the Microsoft Store and search for Python followed by its latest version. It works without error.
** If by chance it does not automatically install on your PC after downloading, click "install on my devices" and select your computer name.
Why can't I install Python directly from the website file? Please note that when trying to install any software/applications from outside Microsoft's trusted locations, there are high chances of user settings interfering with the installation. When coming, for example, from the Microsoft Store, a chance of success is much greater, even without having problems related to User Permission Settings.
Another important thing to point out here is that installing a lot of software from outside Microsoft's trusted platforms can cause you to change some user permissions which can have positive effects with some software and negative effects with others, even with security your own system if you don't know what you're doing.

it's simple , Try Lower Version Like 'Python 3.6' but Download web install.
install it , then install last python version.
your python will update.

I've faced same/similar problem with installing Python 3.9.12 in a clean Windows 8.1 64-bit (VirtualBoxed test environment).
I thought the issue could have been fixed in a newer version of Python, but the freshest 3.10.10 fails with same issue.
The original log isn't available any longer, but luckily it is quoted in another answer, and the following line reveals the real problem:
Applied execute package: core_AllUsers, result: 0x80070643, restart: None
My log looks the same, and if you scroll the log up, you'll discover that core_AllUsers is a UCRT MSI-installer, which is downloaded from Python site (for 3.10.10 64-bit the link may look like https://www.python.org/ftp/python/3.10.10/amd64/ucrt.msi).
If you download it manually (Python installer is smart enough to do a cleanup even if it fails, so you won't find this MSI in a local cache) and run, it will probably crash. And if it is your case, I have a simple solution - just install update KB2999226 (Update for Universal C Runtime) for your OS, which you can download from Microsoft.

I also faced the similar issue. What the trick worked for me is I installed it for the individual user (as earlier installation was for the all users).
So earlier if one has installed it for the all users then install it for the specific user and vice versa.
I know this is not the resolution of the error faced. However, this approach will install Python which is the main motive to achieve.

I encountered the same issue after installing a fresh Windows 8.1 on my PC.
I solved that by using the Python v3.9 web installation file which you can find here.
However, you can choose any other version that has a web installation file
Note: You need internet connection to use this method.

Python 2.7.5 installing issue

I tried to install Python 2.7.5-64 bit in my system. I downloaded the python-2.7.5.amd64.msi from python.org website.
I am facing the following issue while tried installing it.
When clicked on the msi file. there is a window appears saying Change/Repair/Remove
Link to image: http://s22.postimg.org/cw92xphf5/image.jpg
When I chose any option suddenly a window comes saying "Special Thanks to ...." and then Finish option comes
Link to image: http://s7.postimg.org/72rtx8si3/image.jpg

Your computer obviously thinks that that version of python is installed.
Try:
Removing everything to do with python in the control panel.(or python uninstaller in python dir?)
Re-download the installer and try again.
If this fails, I suggest you ask the python team or windows for help, as it is an error.

Pyusb on windows - no backend available

I'm trying to have my Python application interface with an NFC device via USB.
The best option seems to be PyUSB, but I can't get it to connect to the libusb backend.
I keep getting
ValueError: No backend available
I've looked at the stack trace, and found that usb/backend/libusb10.py (which is part of pyusb) is trying to load libusb-1.0.dll to use as the backend, but it can't find it. It's not that it's not in my path, it's not on my computer at all!
I have installed libusb-win32, but the resulting directory only seems to include libusb0.dll. Where is libusb-1.0.dll???!
I would love to know either where to get that dll, or even a different suggestion to get PyUSB to work on Windows 7.

Download and install libusb-win32-devel-filter-1.2.6.0.exe. It should work.

2021 and the problem still occurs on Windows (Windows 10). I solved it by installing pyusb and libusb and adding libusb path to Windows environment:
pip install pyusb
pip install libusb
libusb-1.0.dll will be automatically added to:
\venv\Lib\site-packages\libusb\_platform\_windows\x64
and
\venv\Lib\site-packages\libusb\_platform\_windows\x32
Now just add those paths (the full path) to Windows Path and restart CMD / PyCharm.

I had a similar issue recently trying to talk to a USB device I am developing. I scoured the web looking for libusb-1.0.dll's and had no luck. I found source code, but nothing built and ready to install. I ended up installing the libusb-win32 binaries, which is the libusb0.dll.
PyUSB will search for libusb-1.0, libusb0, and openUSB backends.
libusb0.dll was already on my system, but something was still not set up right, do PyUSB was not working.
I followed the directions here to download and install the driver using the GUI tools provided to install the filter driver, and the INF wizard. Note, it didn't work until I ran the INF wizard.
I'm pretty new to programming and I've found the lack of clear documentation/examples to string this all together rather frustrating.

I am using Python 2.6.5, libusb-win32-device.bin-0.1.12.1 and pyusb-1.0.0-a0 on a windows XP system and kept receiving ValueError: No backend available.
Since there wasn't any real help on the web for this problem I spent a lot of time finding that ctypes util.py uses the Path variable to find the library file. My path did not include windows\system32 and PYUSB didn't find the library. I updated the path variable and now the USB is working.

There's a simpler solution.
Download and unpack to C:\PATH the libusb-1.0.20 from download link
Then try this line:
backend = usb.backend.libusb1.get_backend(find_library=lambda x: "C:\PATH\libusb-1.0.20\MS32\dll\libusb-1.0.dll")
dev = usb.core.find(backend=backend, find_all=True)
Depending on your system, try either MS64 or MS32 version of the .dll
Update of 17/01/2020, after a request to share more code:
import usb.core
import usb.util
from infi.devicemanager import DeviceManager
dm = DeviceManager()
devices = dm.all_devices
for i in devices:
try:
print ('{} : address: {}, bus: {}, location: {}'.format(i.friendly_name, i.address, i.bus_number, i.location))
except Exception:
pass
import usb.backend.libusb1
backend = usb.backend.libusb1.get_backend(find_library=lambda x: "C:\\libusb-1.0.20\\MS32\\dll\\libusb-1.0.dll")
dev = usb.core.find(backend=backend, find_all=True)
def EnumerateUSB(): #I use a simple function that scans all known USB connections and saves their info in the file
with open("EnumerateUSBLog.txt", "w") as wf:
counter = 0
for d in dev:
try:
wf.write("USB Device number " + str(counter) + ":" + "\n")
wf.write(d._get_full_descriptor_str() + "\n")
wf.write(d.get_active_configuration() + "\n")
wf.write("\n")
counter += 1
except NotImplementedError:
wf.write("Device number " + str(counter) + "is busy." + "\n")
wf.write("\n")
counter += 1
except usb.core.USBError:
wf.write("Device number " + str(counter) + " is either disconnected or not found." + "\n")
wf.write("\n")
counter += 1
wf.close()

I had the same problem with Windows 10, both Python 2.7.16 and Python 3.7.2. I installed libusb (through python -m pip install libusb ) but the error message remained. Also, the advice above about installing libusb-win32 did not work for me; neither of the 2 links (original post and #beebek's answer) existed.
What did work, however, is the comment by #user1495323 : I copied libusb-1.0.dll from
C:\Users\username\AppData\Roaming\Python\Python27\site-packages\libusb\_platform\_windows\x64\
to C:\Windows\System32\

download the latest libusb
Download libusb
Copy MS32\dll\libusb-1.0.dll to C:\Windows\SysWOW64
Copy MS64\dll\libusb-1.0.dll to C:\Windows\System32
3.
pip install libusb
Copy MS32\dll\libusb-1.0.dll to C:\Python\Python37-32\Lib\site-packages\libusb_platform_windows\x86
Copy MS64\dll\libusb-1.0.dll to C:\Python\Python37-32\Lib\site-packages\libusb_platform_windows\x64
This method works for me.

Had some problems with backendnotavailable at 2022 when I install pyusb and libusb on my Windows x64.
I've found a way to solve it reading -> Github solve explaining
To solve, first you need copy path to libusb-1.0.dll (..\envs<your_env_name>\Lib\site-packages\libusb_platform_windows\x64) at system's PATH variable.
Secondly restart IDE.
Third try to get_backend use usb.backend:
import usb.core
from usb.backend import libusb1
# it should find libusb-1.0.dll at our path variable
back = libusb1.get_backend()
print(type(back)) # return: <class 'usb.backend.libusb1._LibUSB'>
dev = usb.core.find(backend=back)
print(type(dev)) # return: <class 'usb.core.Device'>
# flag 'find_all=True' would return generator
# reprecent connected usb devices
dev_list = usb.core.find(find_all=True, backend=back)
print(type(dev_list)) # return: <class 'generator'>
If back is a NoneType, that means get_backend() hasn't found libusb-1.0.dll or found the wrong usblib (and that was my problem - I copied atPATH variable path to _x86 file, on my x64 machine).
Another way to solve it -> copy libusb-1.0.dll from (.._x64\libusb-1.0.dll) to (C:\Windows\System32).

"There are two versions of the libusb API: the current libusb-1.0 API, and its legacy predecessor libusb-0.1." (http://www.libusb.org/) "libusb-win32 is a port of the USB library ​libusb-0.1 to the Microsoft Windows operating systems". "Download the latest release tarball" from the same page (1.0.9 is the current version) to have libusb-1.0 equivalent, you'll find a folder Win32, where you'll find your libusb-1.0.dll to play with! You can even build it: http://www.libusb.org/wiki/windows_backend.
EDIT
You have to build it (download from/ http://sourceforge.net/projects/libusb/files/libusb-1.0/) since the tarball is from 2012, while the latest sources are from 2014-06-15.

To connect to your NFC device via USB using PYUSB, you will need to install the backend for that device. I do not think there is any backend for any device other than a libusb device.
To build a backend. You will need to know the driver (.sys file) for your device, so you could write a wrapper DLL to expose functionalities in the device. Your DLL would have to have a method to find device based on PID & VID, another method to open device and another method to send data and so on...

Just in case:
I haven't tried this on Windows but I had to set DYLD_LIBRARY_PATH path to circumvent this error on the Macintosh.
export DYLD_LIBRARY_PATH=/opt/local/lib
Discussion on whether or not to set this variable is here.

The libusb backend is initialized by the python script in /usb path,by loading the binary DLL from Windows PATH,if it's missed or installed by the zadig's dummy DLL,it will complained about this.Because the DLL installed by zadig doesn't exports any symbol to outside wolrd(dummy one I guess)

Is it possible to write a windows service using Python?

Python has a win32service package that seems to allow windows service creation. I have carefully checked available google examples, for example this one:
Is it possible to run a Python script as a service in Windows? If possible, how?
I have placed code into ~/Documents/test.py and executed following under elevated command prompt:
> python test.py install
> python test.py debug
Unfortunately, every example i tried fails with error:
Debugging service TestService - press Ctrl+C to stop.
Error 0xC0000005 - Python could find the service class in the module
AttributeError: 'module' object has no attribute 'AppServerSvc'
(null): (null)
I have tested it with latest version of ActivePython (2.7.2.5 32-bit) on Windows 7 64-bit and Windows 8 64-bit. Of course, if service is started maually via service manager, it will not start either.
Am i doing something wrong or Python is not intended to be used for service creation on modern operating systems? Maybe i need a specific version of windows/python/pywin32? Of course, i can manually test all combinations starting from windows XP but it will take lots of time :(. Maybe someone already has experience with Python and windows services and can hint me what i'm doing wrong?
update
Tested on Windows XP 32-bit virtual macine (same code, same activepython distribution) - same error.

It appears that there is a bug in the ActiveState build for PyWin32. Installing ActiveState python 2.7.2.5 and running the linked sample code above, I get the same error that you are reporting.
But if I download Python 2.7.3 (2.7.2.5 does not seem to be available for download) and add PyWin32 build 214 (ActiveState seems to be using the 214 version of PyWin32). Then everything seems to work just fine. I also tried the latest build of PyWin32 (218) and it also worked correctly.
So I guess you can try reporting the problem to ActiveState (I don't have a support contract with them) and unless you have a requirement for using ActiveState, you can just switch to the standard Python builds.
I have been using services with the standard Python builds for years running on everything from Windows 2000 up to Server 2008 and Windows 7 with no problems. So I have good reason to believe that it will work for you also.
If you want to work with ActiveState to get the problem fixed, then the bug appears to be in their build of PythonService.cpp in the LoadPythonServiceInstance function. I looked at the registry entries that were created and they look fine, it is the PythonService.exe that is failing at loading your class. Based on the error message it appears to have loaded the module correctly and is just having trouble finding the class.