SQL Server 2008 R2 with SP1 on Windows Server 2008
SharePoint 2007 (Dec 09 CU) on Windows Server 2003
"Edit in Report Builder" sends the the browser to
which redirects to
Now the type "Microsoft.ReportingServices.SharePoint.Soap.RSProxyHttpHandler" takes over the request (see httpHandlers section in web.config for WSS virtual directory)
and should send the manifest to the browser from the SSRS server.
This didn´t happen in our environment.
So we reinstalled the SP2 on the SSRS and it solved this problem.
Things to remember:
* The files in "\ISPAI\ReportBuilder" are not the same on MOSS and SSRS.
* "/_vti_bin/ReportServer" have a custom httpHandler definied in web.config.
* Fiddler helps, but only to a certain point.
* Make sure to run the Add-in installation as a Farm administrator.