There is a view named &Gantt Chart in this project which cannot be overwritten
An old historic issue has been cropping up recently on more than one occasion where duplicate view messages appear within Project Professional when opening plans from the server – which is referred as a polluted enterprise global. An example of this message is;
“There is a view named &Gantt Chart in this project which cannot be overwritten.
Press OK to rename it, or press Cancel to cancel opening the project.”
If you open views that do not exist in the Enterprise Global while you have it checked-out, Project will copy over the appropriate view and its table. You can avoid this by always checking the global for pollution prior to checking it back in. To prevent this message from displaying again, continue with the below steps;
When the below error occurs (make a note of the view)
Close the above project, and reload project then open the Enterprise Global to Check it Out
With the checked out global in the background, open the problematic project (maybe all of them) and rename the view when forced too
Change the project plan to another view (not the one mentioned in the error – you cannot delete the view if you are using it)
Go to more views (from the same menu again)
Select the “Checked Out Enterprise Global” option in the right most dialog box
Delete the relevant view (Gantt Chart in this case) from the Checked out Enterprise Global
Do same for entry table if required, then close everything and check it all in.
Simply retest from here.