Nigel - We had a similar problem with a VB .NET application that had some sample files included in the deployment project. If the end user deleted any of the samples after doing an install, every time the application was started using the icon that the install created, the application would try to re-install itself. This didn't happened if the end user just set up a shortcut to the application executable. By default, the deployment sets up an icon which causes a re-install if any application files (any included in the deployment by you or VS 2003) are missing. Check to see if there's a file missing. You can also work around this issue by having your end user set up a regular shortcut. If a missing file not critical to your application is the problem, you can fix this in the generated .msi file using ORCA to modify the type of icon that gets created. - Bob