i cannot edit the design and drag and drop controls from toolbox in webform

Some things stand out here.

1. The screenshot of the editor window shows the HTML view is active, not the designer. The HTML file is in bold.
2. The screenshot also shows that the designer window is what it is trying to render. However there is nothing in the designer which isn't right. I notice that you have a Choose File element at the top of the design window. Is that some controls you put on the page or something else?
3. The Body indicator seems to indicate that maybe you're inheriting from a base control that actually defines the body. In that case there is no place to drag controls from the toolbox from.

Can you share the contents of your ASPX file as HTML? Can you confirm whether you're using an inherited base page or not?

Hi @Omkar Jaiswal,

You should be in Web Live Preview mode.

Change settings: Tools->Options->Web Form Designer-> Select "Legacy Web Form Designer"-> Restart VS.

Best regards,
Lan Huang

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