SharePoint Designer cannot display the item

Problem Description:

When you use Microsoft SharePoint Designer 2010, you may experience one or more of the following issues:

When you try to edit or publish a workflow, you receive one of the following error messages: 

1.      SharePoint Designer cannot display the item.

2.      The list of workflow actions on the server references an assembly that does not exist. Some actions will not be available. 

When you try to create a new list workflow, site workflow, or reusable workflow, you follow the steps to create the workflow. However, after you have completed the steps, the item is not present. 

When you connect to a SharePoint Online site, you receive the following error message:

Microsoft SharePoint Designer cannot be used to edit web sites on servers different from SharePoint Server 2010.

  

When you connect to a SharePoint site, you receive the following error message:

This web site has been configured to disallow editing with SharePoint Designer. 

Resolution:

To resolve these issues, install Microsoft SharePoint Designer 2013. SharePoint Designer 2013 is available at the following Microsoft website:

http://www.microsoft.com/en-us/download/details.aspx?id=35491

Note:- You may install SharePoint Designer 2013 alongside SharePoint Designer 2010. However, we recommend that you uninstall SharePoint Designer 2010 before you install SharePoint Designer 2013.

Important Guidelines:

1.      You experience these issues if one or more of the following conditions are true:

2.      You have received the most recent update to the Office 365 SharePoint Online service. 

3.      You have upgraded your on-premises installation of Microsoft SharePoint Server 2010 to Microsoft SharePoint Server 2013. 

4.      You have upgraded your installation of Microsoft SharePoint Foundation 2010 to Microsoft SharePoint Foundation 2013. 

If you have any queries/questions regarding the above mentioned information then please let me know. I would be more than happy to help you as well as resolves your issuesJJ