I've been trying to install SQL Server 2008 R2 x64 Developer Edition on Windows 7 x64 Enterprise edition since shortly after R2 was released. Initially I was blocked by the ENU localization problem (http://connect.microsoft.com/SQLServer/feedback/details/557556/sql-server-2008-r2-setup-has-encountered-an-error), but I recently revisited this and overwriting the setup.rll with the Evaluation edition version worked around it.
Now I am getting stopped by the above error (setup "attempted to perform an unauthorized operation") roughly halfway through the setup process. The setup log Details.txt indicates that the issue is Inner exception type: System.UnauthorizedAccessException during a ReplaceAccountWithSidInSddl (Attempting to replace account with sid in security descriptor) operation at Microsoft.SqlServer.Configuration.Sco.InternalRegistryKey.SetSecurityDescriptor, apparently in or around the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server subkey. This error is occurring during a fresh install, but I've also tried installing SQL Server 2008 (installed with no problem) and then upgrading to R2, with the same error. I've been running Setup as administrator, and Data Execution Prevention is turned off except for essential Windows components. I've tried using Process Monitor to see which subkeys are being accessed, but all the ones I see seem to have full control assigned to administrators, which should allow setup to do what it needs to do.
Any help would be greatly appreciated, as this has now taken up multiple days of working time and there doesn't seem to be anything on the Web matching this issue.
Thanks in advance,
Brian
BC