.NET 2008 deployment kit

I am trying to make a deployment kit for my project in VB.NET 2008 and everything seems to work ok, but when I upgrade my version, the setup kit does not overwrite my prevous installation. I checked and everything seems to be ok in my configuration ( I have RemovePreviousVersion set to true and DetectNewerInstallation to true)
Is this a known issue with .NET 2008, because I never had that problem with .2005 and I have this problem with every .2008 project I made.

Thank you