If you can’t connect to your SharePoint server using SharePoint designer, one of the possibilities of what happened is that you have a remove tag added after after the add ScriptResource.axd. To solve try this:
– Use fiddler2 to determine issue. Download it from here www.fiddler2.com
– Check the error messages
– If you see access denied (http response code 401) to /_vti_bin/usergroup.asmx then it might be that you added AJAX support and the entries are in incorrect order in the web config
Description of the problem
<remove verb=”*” path=”*.asmx” /> is inserted automatically after <add verb=”GET,HEAD” path=”ScriptResource.axd” <add verb=”*” path=”*.asmx” validate=”false” type=”System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35″/>
This Means the .asmx pages do not work on the sharepoint server after adding the feature. This also prevents you edit the site using sharepoint designer because /_vti_bin/usergroup.asmx will give a 401 access denied error.
The issue is here:
<remove verb=”*” path=”*.asmx” />
Simply remove the tag and it will work
Check out the resolution here http://features.codeplex.com/WorkItem/View.aspx?WorkItemId=6623