…created during service pack 1 (SP1) installation via PowerShell. Run Powershell in elevated mode (run as administrator) and type: Dism.exe /online /cleanup-image /spsuperseded You should earn more than 1Gb of disk space.

if you need to wok on this, I think that the following post is a must to have read: http://blogs.iis.net/samzhang/archive/2009/12/16/how-to-build-scalable-and-robust-live-smooth-streaming-server-solutions.aspx