SharePoint Designer Server Error: The attempted operation is prohibited because it exceeds the list view threshold enforced by the administrator

SharePoint Designer Server Error: The attempted operation is prohibited because it exceeds the list view threshold enforced by the administrator.

If you see the error below:

 

It means you have to change your Listview threshold as follows:

Change the List View Threshold option:

1. Login to Central Admininstration;
2. Go to Application Management -> Manage Web Applications;
3. Select SharePoint Central Administration WebApplication;
4. In the ribbon above, click General Settings. That will bring down a menu, from which you should pick Resource Throttling;
5. Change the List View Threshold option 30000 and press OK;

This solved my issue. I hope it resolves yours too.