User61956409 posted
Hi dudirudiana,
Firstly, please make sure if you enter correct URL in your browser. You can check your
Project URL (I’m using VS2017, right-click Project and chose
Property and in Web tab I can find it).

Secondly, please check if your web application is running on IIS express.

Besides, you can try to right click your webpagename.aspx and click "View in Browser" to check if it can be displayed in your browser.
With Regards,
Fei Han