Unable to call ASP.NET Web API hosted on IIS 10, Windows 10

Question

I have created ASP.NET API endpoints on my Windows 10 PC, hosted on IIS. Using Chrome's extension app, Postman, I could call the API internally within the same machine (using localhost and even my own local IP). Example:

http://localhost/UserService/api/user/getByUsername?username=abc

and

http://192.168.0.160/UserService/api/user/getByUsername?username=abc

Then I tried using another PC (Windows 7) to connect to the same Wifi LAN that my Windows 10 PC is connected to, and attempted to call the above example URL via Postman, but it did not get through (getting "Could not get any response"error). The Windows 7 PC could not call API hosted on Windows 10 PC.

However, when I reversed the setting ie to host on Windows 7's IIS (version 7.5) and used Windows 10 PC to call instead, no issue found.

What went wrong?? Is it due to some Firewall settings?

Answer 1

A few things to check in Windows Firewall with Advanced Security :

• Have you enabled the World Wide Web Services (HTTP Traffic-In) rule in Windows firewall exceptions?
• Do you have any entries in the Remote Computers tab?
• Is the action Allow the connection ?
• What is the content of your Advanced tab like?

EDIT

Based on your comments, the issue is indeed a firewall issue, but not Windows Firewall with Advanced Security . McAfee firewall is blocking external access to port 80. Add an exception to McAfee to allow port 80, and possibly 443. Consult McAfee's knowledge base.

Answer 2

With great help from @reckface, the root cause is found, which is in fact the McAfee antivirus itself. After exploring around the UI, I found the setting to allow incoming traffic for certain port(s) without needing to turn off firewall setting entirely.

With "Web Server (HTTP) Port 80" enabled on the UI, I can now access API's from another PC.