http://blog.flaphead.dns2go.com/archive/2008/03/13/exchange-server-2007-service-pack-1-ru1.aspxOkay so it's not difficult to install, but as ever I want to share the steps we have used successfully. So before you start yeah a reboot to start with, as we have seen that is just a better place to start the installation! Generally it takes 10-15minsenCommunityServer 2.1 SP2 (Build: 61129.2)http://blog.flaphead.dns2go.com/archive/2008/03/13/exchange-server-2007-service-pack-1-ru1.aspx#9086Fri, 14 Mar 2008 19:53:03 GMTdfd37a73-98d8-4eec-a8b7-87a183efa840:9086subject: exchange<p>Gaps found in Microsoft Exchange API documentation Windows Server 2008 &amp;amp; Exchange Backup I do not</p>http://blog.flaphead.dns2go.com/archive/2008/03/13/exchange-server-2007-service-pack-1-ru1.aspx#9091Fri, 14 Mar 2008 19:56:53 GMTdfd37a73-98d8-4eec-a8b7-87a183efa840:9091subject: exchange<p>Gaps found in Microsoft Exchange API documentation Windows Server 2008 &amp;amp; Exchange Backup I do not</p>http://blog.flaphead.dns2go.com/archive/2008/03/13/exchange-server-2007-service-pack-1-ru1.aspx#9095Sat, 15 Mar 2008 11:32:48 GMTdfd37a73-98d8-4eec-a8b7-87a183efa840:9095subject: exchange<p>Gaps found in Microsoft Exchange API documentation Windows Server 2008 &amp;amp; Exchange Backup I do not</p>