After a lot of editing of my build templates (I recreated them in 2012 to avoid any issues.. but then I suppose I got sloppy and simply copy/pasted whole blocks from the old workflow, and I suppose that must have completely destroyed my versioning) I now have problems with just one build definition based on the build template I edited. (All other ones seem to be working fine.. so I suppose that one got a problem during all the editing. (I was mostly adding and removing Version=11.0.0.0 to the assemblies in the build template))
The exact error is:
Parameter Items to Build: cannot convert value 'Microsoft.TeamFoundation.Build.Workflow.Activities.BuildSettings' of type Microsoft.TeamFoundation.Build.Workflow.Activities.BuildSettings to type Microsoft.TeamFoundation.Build.Workflow.Activities.Buildsettings, reset to default.
It is displayed when editing the build definition and wanting to select the project/solution and configuration to build. Actually, with this now I cannot save (without error) any more and the value gets deleted again.
(I am using VS 2012 (VS 2010 still installed) against TFS 2012.)
How to fix?
Open up your XAML and look at the xmlns's on the Activity root node:
Here's a snipped version of mine:
<Activity mc:Ignorable="sads sap sap2010" <!--Removed-->
xmlns="http://schemas.microsoft.com/netfx/2009/xaml/activities"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:mt="clr-namespace:Microsoft.TeamFoundation;assembly=Microsoft.TeamFoundation.Common"
xmlns:mtbc="clr-namespace:Microsoft.TeamFoundation.Build.Client;assembly=Microsoft.TeamFoundation.Build.Client"
xmlns:mtbw="clr-namespace:Microsoft.TeamFoundation.Build.Workflow;assembly=Microsoft.TeamFoundation.Build.Workflow"
xmlns:mtbwa="clr-namespace:Microsoft.TeamFoundation.Build.Workflow.Activities;assembly=Microsoft.TeamFoundation.Build.Workflow"
xmlns:mtbwt="clr-namespace:Microsoft.TeamFoundation.Build.Workflow.Tracking;assembly=Microsoft.TeamFoundation.Build.Workflow"
xmlns:mttbb="clr-namespace:Microsoft.TeamFoundation.TestImpact.BuildIntegration.BuildActivities;assembly=Microsoft.TeamFoundation.TestImpact.BuildIntegration"
xmlns:mtvc="clr-namespace:Microsoft.TeamFoundation.VersionControl.Client;assembly=Microsoft.TeamFoundation.VersionControl.Client"
xmlns:mtvc1="clr-namespace:Microsoft.TeamFoundation.VersionControl.Common;assembly=Microsoft.TeamFoundation.VersionControl.Common"
Look for Version Specific references (usually "10.0" or "11.0") and remove them so they look like the ones I have above.
Also, check you project references and ensure that they are not Version Specific.