Windows服务器IIS部署Plotly-Dash时Flask读取WSGI处理器报错求助

Hey everyone, I'm stuck trying to get a Plotly-Dash app up and running on my Windows Server with IIS. Every time I deploy it, I hit the error "Error reading WSGI handler"—but here's the weird part: a basic Flask test app works perfectly fine under the same IIS setup.

Let me break down what I've done so far:

• I followed the Flask on IIS guide to the letter, only changing the website's file path within the wwwroot folder.
• The basic Flask app (code below) loads without any issues, so I know my IIS/FastCGI configuration is at least partially working.
• As soon as I swap in my Dash application, that WSGI handler error pops up immediately.

Here's the working basic Flask code:

from flask import Flask
app = Flask(__name__)

@app.route("/")
def hello():
    return "Hello from FastCGI via IIS!"

if __name__ == "__main__":
    app.run()

My Dash app follows the standard structure, something like this:

import dash
from dash import html, dcc

app = dash.Dash(__name__)

app.layout = html.Div([
    html.H1("My Test Dash App"),
    dcc.Graph(figure={"data": [{"x": [1,2,3], "y": [4,5,6], "type": "bar"}]})
])

if __name__ == "__main__":
    app.run_server(debug=True)

I've verified all required packages (Flask, dash, waitress, wfastcgi) are installed in the server's Python environment, the application pool is using the correct Python version, and folder permissions on wwwroot are set to allow IIS access.

Has anyone run into this exact problem when deploying Dash on IIS? Any tips on how to debug this WSGI handler error, or common misconfigurations I might be missing?

内容的提问来源于stack exchange，提问作者roastbeeef