from flask import Flask

app = Flask(__name__)

@app.route("/")
def hello_world():
    return "<p>Hello, World!</p>"

Execute the flask python file:
flask --app [python filename] run

• Open "Turn Windows Feature on or off" and enable "CGI' under "IIS/WWW Services/Application Development Features"

• Execute pip install wfastcgi to install wfastcgi
• Go to your Python\Scripts folder
  You may find the Python folder location by where python
  Then execute the wfastcgi-enable.exe
  Or you may execute wfastcgi wfastcgi-enable to enable wfastcgi

Add Permission for IUSR in order for IIS to access your application folder

icacls . /grant "NT AUTHORITY\IUSR:(OI)(CI)(RX)"
icacls . /grant "Builtin\IIS_IUSRS:(OI)(CI)(RX)"

Or you can add permission using the GUI
Search user "IUSR" and "IIS_IUSRS" and grant the permission

When wfastcgi enabled, you should able to find the "FastCGI Settings" in your IIS root

In your Site Application, open "Handler Mappings" page and select "Add Module Mapping..." on Actions

Request path:
*
Module:
FastCgiModule
Executable (optional):
[YOUR_PYTHON_EXE_PATH]|[YOUR_WFASTCGI_EXE_PATH]
Name:
FlaskHandler

Click the "Request Restrictions..." button
Uncheck the "Invoke handler only if request is mapped to:" checkbox

Back to the IIS root FastCGI Settings, and you should able to see record which "Full Path" and "Arguments" defined with your Python and wfastcgi path
Double click to Edit the record
Edit the Environment Variables under FastCGI Properties

Create 2 new members
Name: PYTHONPATH
Value: [YOUR_APPLICATION_ROOT_FOLDER]

Name: WSGI_HANDLER
Value: [YOUR_ENTRY_PY_FILE_NAME].app

Deploy a Python Flask Application in IIS Server and run on machine IP address
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