I created a simple visual web part(farm solution only) with Hello World text in it and added in a
SitePage through browser which is working fine.
Now when I open that page in SP Designer 2013 and just saves it without modifying anything on page, and tries to preview it in browser, it gives error.
Error Web Part Error: Unknown server tag 'wpns0:TestVisualWebPartACE'. Correlation ID: 63c08e9d-2313-9032-f671-d6883bc7b7c2
It gave same error when I re-inserted that web part in that page through SP Designer.
Can anyone please suggest what might be the issue?