http://blogs.msdn.com/jonwis/archive/tags/update/default.aspxTags: updateen-USCommunityServer 2.1 SP1 (Build: 61025.2)http://blogs.msdn.com/jonwis/archive/2009/01/13/what-s-winsxs-manifestcache-lt-something-gt-blobs-bin.aspxWed, 14 Jan 2009 01:00:00 GMT91d46819-8472-40ad-a661-2c78acb4018c:9317304jonwis0http://blogs.msdn.com/jonwis/comments/9317304.aspxhttp://blogs.msdn.com/jonwis/commentrss.aspx?PostID=9317304<P>Glenn writes:</P> <BLOCKQUOTE> <P>"What is the c:\windows\winsxs\manifestcache\6.0.6001.18000_001c50b5_blobs.bin file and why is it taking up 156Mb on my hard drive? Do I really need a file this big?"</P></BLOCKQUOTE> <P>That file is used by the Windows Update mechanisms in Vista.&nbsp; It acts like a cache and is capped at a certain size, but it's safe to delete.&nbsp; The next time you turn on or off Windows optional features or take updates from Windows Update it'll reappear.&nbsp;The file will be recreated as necessary to help the servicing system do its work.&nbsp; Maybe in the future it'll be added to the disk-cleaup wizard, but it noticably increases the performance of servicing operations while it's there.</P> <P>Of course, actually deleting the file is left as an excercise to the reader.</P><img src="http://blogs.msdn.com/aggbug.aspx?PostID=9317304" width="1" height="1">servicingblobs.binupdatemanifestcache