Keeping to my mantra of Forewarned is Forearmed:

During the last two years i have demonstrating how to do "ClickOnce" applications with the .NET Framework 1.1. 

These applications were referred to as "Zero Touch" or "HREF to EXE" where security was typically accomplished through CAS and code signing , unfortunately i just found out  this week that many of these applications will get broken with the installation of the .NET Framework 2.0.  The choices right now are:

1.  Have your customers add the installation server to the their trusted sites.

2. Rebuild the application in VS 2005 and use ClickOnce.

3. Add a registy setting on the client computer

I have asked PSS to escalate the case to compatibilty team to see if we can get more information

For more information please see http://lab.msdn.microsoft.com/ProductFeedback/viewfeedback.aspx?feedbackid=ef4ae9a2-1d40-4241-aca4-61d579929793