Hi Shriram,
This problem might be caused by an internal problem in Unity. Whenever you see an error message mentioning UnityEditor and something with Layout, please try the following: Go to Window > Layouts and select “Default”. If you created your own layout, remove that, select “Default”, rearrange the windows and save it again.
If the issue persists: In which course and lecture are you?
See also:
- Forum User Guides : How to mark a topic as solved