Hi, I’m trying to set up DeepLabCut on a Windows workstation for behavior analysis, and I ran into a GUI issue when installing from the YAML environment file.

On macOS, the YAML-based installation works fine.
On Windows, the environment is created successfully, but the GUI does not launch.

I created the environment from the provided YAML file and activated it, then ran: python -m deeplabcut

DeepLabCut starts loading, but then it falls back to light mode and GUI functionality is unavailable:
Loading DLC 3.0.0rc13...
DLC loaded in light mode; you cannot use any GUI (labeling, relabeling and standalone GUI)

Then I get a Qt-related error: qtpy.QtBindingsNotFoundError: No Qt bindings could be found

I checked the environment, and qtpy, pyside6, pyside6-addons, pyside6-essentials, and qt-main were all present.
However, the following imports fail on Windows:
python -c "from PySide6 import QtCore; print(QtCore.file); print(QtCore.qVersion())"
python -c "from PySide6 import QtWidgets; print(QtWidgets.QApplication)"

ImportError: DLL load failed while importing QtCore: The specified procedure could not be found.
ImportError: DLL load failed while importing QtWidgets: The specified procedure could not be found.

So it seems that:

the package is installed, but the actual Qt DLLs / bindings are not loading correctly on Windows, which causes qtpy to think that no usable Qt binding is available.

-Environment notes
Windows: GUI fails after YAML install
macOS: same YAML-based workflow works fine
GPU is AMD Radeon RX 550, so I am using CPU only
Miniconda is being used

python and conda paths look correct in the environment

Has anyone seen this specific issue on Windows with YAML-based installation?

I’m mainly trying to understand:

1. whether this is a known PySide6 / Qt DLL issue on Windows,

2. whether the YAML file pulls a problematic Qt/PySide combination on Windows,

3. and whether there is a recommended fix for Windows besides manually rebuilding the environment.

Any suggestions would be appreciated.