I've never seen this before. Please can somebody shed some light on it for me. I've just done a clean install of Vista Business 64, followed by Firefox, followed by VS 2008 SP1, from an MSDN DVD. Late in the installation - I wasn't watching so didn't see when - I suddenly got a screenful of fail.
The first message in the error log is:
setup.exe: [2] ISetupComponent::Pre/Post/Install() failed in ISetupManager::InternalInstallManager() with HRESULT -2147023293
Google yields very, very few relevant results.