Seeing the following ClickOnce error log? Well your ClickOnce manifests are not signed ...
- Exception reading manifest from http://foo.application: the manifest could be invalid or the file could not be opened.
--- Inner Exception ---
System.Deployment.Application.ValidationFailedException (Unknown subtype)
- The manifest has no XML signature.
But I did sign the manifest while publishing in VS?
Check if your project includes assemblies with spaces in their name.
There is a known Beta2 bug which causes VS to barf on signing manifest if the project includes Assemblies with spaces in the name.
Renaming the Assemblies in the easy workaround.