How to Prevent SharePoint 2010 users from using SharePoint Designer

Problem

SharePoint Sites can be edited using SharePoint Designer for customizing the user interface and other purposes. But at times, it could potentially affect the performance of sites. In such cases, some administrators prefer to not to allow customization using SharePoint Designer.

Solution

Not only can SharePoint 2010 limit users from using SharePoint Designer 2010 but it can also stop users from detaching pages, customizing the master page and layout pages and it even preventing the change of the Web Site URL Structure. In this article, we will look into how to stop users from editing the site using SharePoint Designer 2010.

Go to Central Administration -> Application Management:



Under Web Application, click Manage Web Applications.



Select the application on which you want to restrict all users from using SharePoint Designer 2010. Click on the application name.



A ribbon will be available at the top once you select the application. Click on general settings and then on SharePoint Designer.



A box will be prompted with some options.To restrict user, uncheck the "Enable SharePoint Designer" checkbox. Click OK.



Now go to any site page. Click on the "Page" Tab on Ribbon. Click on Edit and then on "Edit in SharePoint Designer". Enter the credentials. Once you enter the needed credentials, you will be prompted with an error describing that the user is not allowed to edit site in SharePoint Designer (see image below).



One can use this feature to stop every user from accessing the SharePoint site using SharePoint Designer.
Reference:

http://www.mssharepointtips.com/tip.asp?id=1091