After installing Rollup 5 on Exchange 2007, services dependent on AD Topology Service do not start automatically during boot. However they can be started manually after boot. Any ideas why?

Is your exchange server also a Domain Controller? http://support.microsoft.com/kb/940845 Deli

I am having a similiar issue. I installed rollup 5 on a CAS server and a combined CAS/HT/MB server in a testing environment. The System Attendent, Topology Service and Information Store would start, but not the other services.Manually starting the services does NOT work. "service does not start in a timely fashion" Removing Rollup 5 ( back to Rollup 3 ) fixed the services.

I assume that all previous updates have been removed before installing rollup 5?

Please see http://forums.microsoft.com/TechNet/ShowPost.aspx?PostID=2364090&SiteID=17for a solution. You have run into the same problem we did. It is a problem with the new Exchange 2007 executables and the .Net Framework 2.0 autheticode signature checking. You need to get a patch from MS Support (not released to the public) to add a new config setting for the .Net framework. After changing the .config files for the services to tell .Net not to check the authenticode signatures, your services will start at boot.