I'm using Visual studio 2017 for past few years. Now, first line of all aspx page shows below error on all my existing web applications.
Runtime error: Object reference not set to an instance of an object.
Also I tried to create a new project. It is also showing same issue. And when I try to run those project, It shows "localhost refused to connect."
I have tried many solutions from web. But couldn't solve the issue. What I tried are,
- Deleted .vs folder
- Deleted .suo file
- Clean and rebuild
- Uninstalled VS 2017 and reinstalled. Now I'm using version 15.9.34
UPDATE 1
I have uninstalled VS 2017 and installed VS 2019. Still showing same error for website projects. I have installed .NET frame work version V4.0.30319 and ASP.NET and web development tools.