401.3 Forbidden IIS error

Question

I'm using IIS to run a Python script and I keep getting 401.3 Forbidden error. I've tried switching from IUSR to Application Pool Identity. I've added IUSR to the list of users, given read, execute and folder access. Followed solutions from Stackoverflow but it didn't help. Can anyone please tell me what is the cause of this error? Thank you.

Answer 1

I think 401.3 is an unauthorised error where special permission is required to access data.
You need to make sure that Your application pool and website both are running under same Identity. Or
You need to enable your anonymous authentication and set anonymous user identity.