Hi,
When we debug a website from Visual Studio, the Visual Studio debugger will attach to IE process, and debugger will stop debugging when we close this process.
In your case, please make sure that close the process of IE ( Not tab of IE) that the debugger attaches. You can view the Task Manager to check if it is closed.
You also can check if the debugger detaches the IE process from Visual Studio after closing IE by Debug -> Attach to Process -> Check if the IE is still attached by Debugger.
When you started debugging, was the application loaded in existed IE or new instance of IE? You can set the Visual Studio to open the page in new instance of IE (Right Click an aspx page -> Select Browse With -> Set the IE as default browser).
If this doesn’t help you, please feel free to let me know.
I hope this helps.
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