What happened?
Package
Stable Diffusion WebUI Forge - Neo (also reproducible with Stable Diffusion WebUI Forge)
When did the issue occur?
Installing the Package
What GPU / hardware type are you using?
RTX 5090, AMD64 Family 26 Model 68 (Ryzen), Windows 11
What happened?
All package installations fail with the following error. This started after manually installing Style-Bert-VITS2 outside of Stability Matrix (which modified the system Python 3.10 environment).
Even after:
- Deleting and re-downloading Assets\Python310
- Uninstalling system Python 3.10 completely
- Clearing uv cache at %LOCALAPPDATA%\uv
- Reinstalling Stability Matrix
The error persists.
Error Log
Could not install forge-neo (StabilityMatrix.Core.Exceptions.ProcessException: pip install failed with code 2: 'error: Failed to inspect Python interpreter from provided path at venv\Scripts\python.exe
Caused by: Querying Python at H:\StabilityMatrix-win-x64\Data\Packages\Stable Diffusion WebUI Forge - Neo\venv\Scripts\python.exe failed with exit status exit code: 1
[stderr]
AttributeError: module 'main' has no attribute 'file'. Did you mean: 'name'?
Root Cause Analysis
uv 0.9.30 (bundled with Stability Matrix 2.15.6) inspects the venv Python interpreter using:
python.exe -c "import sys; print(sys.file)"
However, __file__ is not defined when Python is run with -c flag — this is standard Python behavior. This causes uv to fail when inspecting any venv interpreter.
Steps to Reproduce
- Install system Python 3.10 and add to PATH
- Use system Python to install packages (e.g. Style-Bert-VITS2)
- Remove system Python from PATH or uninstall it
- Try to install any package in Stability Matrix 2.15.6
Expected Behavior
Package installation should succeed regardless of system Python state.
Stability Matrix Version
2.15.6
Additional Info
- uv version bundled: 0.9.30
- uv 0.11.4 has the same behavior when called by Stability Matrix (SM overwrites uv.exe on startup)
- Both Forge Neo and ComfyUI installations fail with identical errors
Steps to reproduce
No response
Relevant logs
Version
v2.15.6
What Operating System are you using?
Windows
What happened?
Package
Stable Diffusion WebUI Forge - Neo (also reproducible with Stable Diffusion WebUI Forge)
When did the issue occur?
Installing the Package
What GPU / hardware type are you using?
RTX 5090, AMD64 Family 26 Model 68 (Ryzen), Windows 11
What happened?
All package installations fail with the following error. This started after manually installing Style-Bert-VITS2 outside of Stability Matrix (which modified the system Python 3.10 environment).
Even after:
The error persists.
Error Log
Could not install forge-neo (StabilityMatrix.Core.Exceptions.ProcessException: pip install failed with code 2: 'error: Failed to inspect Python interpreter from provided path at venv\Scripts\python.exe
Caused by: Querying Python at H:\StabilityMatrix-win-x64\Data\Packages\Stable Diffusion WebUI Forge - Neo\venv\Scripts\python.exe failed with exit status exit code: 1
[stderr]
AttributeError: module 'main' has no attribute 'file'. Did you mean: 'name'?
Root Cause Analysis
uv 0.9.30 (bundled with Stability Matrix 2.15.6) inspects the venv Python interpreter using:
python.exe -c "import sys; print(sys.file)"
However,
__file__is not defined when Python is run with-cflag — this is standard Python behavior. This causes uv to fail when inspecting any venv interpreter.Steps to Reproduce
Expected Behavior
Package installation should succeed regardless of system Python state.
Stability Matrix Version
2.15.6
Additional Info
Steps to reproduce
No response
Relevant logs
Version
v2.15.6
What Operating System are you using?
Windows