You must have the Enterprise, Developer, Standard, or Evaluation edition of SQL Server to use Report Builder.
The client computer must have the Microsoft .NET Framework 2.0 installed. The .NET Framework provides the infrastructure for running ClickOnce applications.
You must use Microsoft Internet Explorer 6.0 or later.
Report Builder always runs in full trust; you cannot configure it to run in partial trust. In previous releases, it was possible to run Report Builder in partial trust, but that option is not supported in SQL Server 2008.