Release management causing build to fail

I'm trying to configure release management to run with our TFS. Upon building I get an exception and cannot work out how to fix it:

Exception Message: Release build failed (type Exception) Exception Stack Trace: at System.Activities.Statements.Throw.Execute(CodeActivityContext context) at System.Activities.CodeActivity.InternalExecute(ActivityInstance instance, ActivityExecutor executor, BookmarkManager bookmarkManager) at System.Activities.Runtime.ActivityExecutor.ExecuteActivityWorkItem.ExecuteBody(ActivityExecutor executor, BookmarkManager bookmarkManager, Location resultLocation)

The releases do not appear on the release management client. So i can only assume it cant reach the release management server? Is there anyway to get more debug information?

I cant find much information on this?

In addition to what Wouter said (Hi Wouter! :)):

1. Make sure the Release Management client is installed on your build agent. Once it's installed, make sure you've run it and connected it to your RM server. The account you do this as does not matter.
2. Make sure the Build service account (the account that all of your builds run as) is a Service User in Release Management.