python3.7.0+opencv_python3.4.2.17, "from .cv2 import *" says "DLL load failed:"

[tianxiawuzhe]

I install python3.7 and opencv-python 3.4.2.17 (using pip install), all are ok.
when "import cv2", it says:
Traceback (most recent call last):
File "", line 1, in
File "XXXX\lib\site-packages\cv2_init_.py", line 3, in
from .cv2 import *
ImportError: DLL load failed: could not find this module.
I read some solutions, but not resolved.
I install python3.6.3 and opencv-python 3.4.0.12 on the same windows 7. it runs ok.
That means, the os env could be ok.
any suguesstions?

[tianxiawuzhe]

Thanks. Resolved!
by #114, I download depends from http://www.dependencywalker.com/.
Shows:
API-MS-WIN-DOWNLEVEL-SHLWAPI-L1-1-0.DLL
PYTHON37.DLL
IESHIMS.DLL
Error open File.
Then, I compare the dependency of cv2.cp36-win32.pyd and cv2.cp37-win32.pyd.
may be API-MS-WIN-DOWNLEVEL-SHLWAPI-L1-1-0.DLL is missing on windows 7.
Download api-ms-win-downlevel-shlwapi-l1-1-0.dll from 'https://www.dll-files.com/api-ms-win-downlevel-shlwapi-l1-1-0.dll.html', choose x86 version.
copy it to C:\Windows\System32 and C:\Windows\SysWOW64.
And 'import cv2' is ok.
Thanks very much!

[wb666greene]

@tianxiawuzhe

Which version of the dll did you download? There are 5 on the site!

Were you using 32 or 64 bit Python 3.7?

I'm trying to port some Linux python code to windows 7, all the other pip installs seem fine, but I'm dead before I start without import cv2 working.

I've been given a 64-bit Windows 7 Professional machine to work with, so I've startedwith the 64-bit Python3.7

[wb666greene]

Followup.

I needed the 64-bit version 6.3.9600.16384:
https://www.dll-files.com/download/9cada7cc00753250c1beda32c23e22ee/api-ms-win-downlevel-shlwapi-l1-1-0.dll.html?c=NUlOeGlpQkZoankwNVNGVmUveUZ2UT09

Added it to both system32 and syswow64

I'm using 64-bit python 3.7.0 on windows 7 professional. I was getting depressed as it was the 4th one I tried :(

At least now I've reached first base.

[tianxiawuzhe]

@tianxiawuzhe

Which version of the dll did you download? There are 5 on the site!

Were you using 32 or 64 bit Python 3.7?

I'm trying to port some Linux python code to windows 7, all the other pip installs seem fine, but I'm dead before I start without import cv2 working.

I've been given a 64-bit Windows 7 Professional machine to work with, so I've startedwith the 64-bit Python3.7

Sorry for late.
windows7 professional-64bit, python3.7-32bit ( installed by anaconda)
dll is the first one on 'https://www.dll-files.com/api-ms-win-downlevel-shlwapi-l1-1-0.dll.html' (17.3kb)
maybe you should download x64 dll for python3.7.

[wb666greene]

I thought I posted a follow-up after I started trying them all in sequence and got it to work. But thanks for the reply.

…

On Thu, Sep 13, 2018 at 1:08 AM tianxiawuzhe ***@***.***> wrote: @tianxiawuzhe <https://github.com/tianxiawuzhe> Which version of the dll did you download? There are 5 on the site! Were you using 32 or 64 bit Python 3.7? I'm trying to port some Linux python code to windows 7, all the other pip installs seem fine, but I'm dead before I start without import cv2 working. I've been given a 64-bit Windows 7 Professional machine to work with, so I've startedwith the 64-bit Python3.7 Sorry for late. windows7 professional-64bit, python3.7-32bit ( installed by anaconda) dll is the first one on ' https://www.dll-files.com/api-ms-win-downlevel-shlwapi-l1-1-0.dll.html' (17.3kb) maybe you should download x64 dll for python3.7. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#116 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AeB7JjJcxvHi0mngiXyeu6B7lwuOkpULks5uafZugaJpZM4V1Aea> .

[Vhati]

Encountered this and fixed it by downloading the missing dll, mentioned above.
"api-ms-win-downlevel-shlwapi-l1-1-0.dll" v10.0.14393.0 32bit (17.3 kb)

Win7 Pro 64bit, Python 3.6.5 32bit (without Anaconda), opencv-python 3.4.3.18.

Already had the dependencies recommended on PyPI: "Visual C++ redistributable 2015" and "Universal C Runtime" update.

#!/usr/bin/env python3
import os

# Include a bundled dll in the search path.
script_dir = os.path.realpath( os.path.dirname( __file__ ) )
os.environ['PATH'] = os.environ['PATH'] + os.pathsep + script_dir
import cv2

# Do stuff with OpenCV...

[azhaoaigaga]

@wb666greene Did it work out? I used Windows server 2008, and the above problems also appeared, but I did not lose the api-ms-win-downlevel-shlwapi-l1-1-0 in system32 and syswow64. Do I still need to download and replace the DLL, or do I have other solutions? This has been bothering me for several days.

[wb666greene]

@azhaoaigaga As far as I can tell it did. I'm not much of a Windows user anymore, I was helping a friend setup a system. This was a 64-bit system, you may need differnet for 32-bit.
I ultimately needed to install:
api-ms-win-downlevel-shlwapi-l1-1-0.dll
Windows6.1-KB2999226-x64.msu
vc_redist.x64.exe
vc_redist.x86.exe

To get everything to work.
Hope this helps, but I haven't touched a Windows system since I initially posted and eventually got his Python3 system working.

[skvark]

Windows server is probably missing some dependencies since it's headless by default. Never download DLL files from the internet, they are most likely malware / viruses. You could try to install the opencv-python-headless version which is targeted for headless server environments. Just remember to uninstall opencv-python first.

If that does not work, the issue is probably related to other missing DLL files which are not present on Windows Server versions. See for example https://withinrafael.com/2017/09/09/windows-container-app-compat-opencv-python/. In that case it might be that you have to build OpenCV manually and disable some Cmake flags to turn off features which are not supported by Windows Server 2008.

[azhaoaigaga]

@wb666greene @skvark thanks,i‘ll try.