qt.qpa.plugin: Could not find the Qt platform plugin "windows" in "" This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

[SaptNskr2023]

Ran pip install --force-reinstall opencv-python-headless==4.1.2.30
but the error still pops up. Please help. Thanks.

[rmnegovan]

I had this exact same issue

What ended up working was the following:

1. COPY every .dll file from this folder:
   ...\anaconda\Lib\site-packages\PyQt5\Qt5\plugins\platforms
   into this folder:
   ...\anaconda\Library\plugins\platforms

2. Go to Control Panel/System/Advanced System Settings/Environment Variables
   and set a new environment variable QT_PLUGIN_PATH
   with the value ...\anaconda\Library\plugins

IMPORTANT NOTE: pay attention to the paths, my anaconda is installed in program files, yours might be somewhere else. Type the full path in at every step.

Godspeed! Inshallah it resolves your issues!