Hello everyone, I've created an upgrade for my application in InstallShield 2015. It's a .NET MVC software with multiple projects like the APIService project , WEBUI project. The problem occurs when the InstallShield created executable is run for the APIService project- it should delete the old files and get new files in the project folder on the local machine it is installing on. All the other projects are upgraded successfully. The installer works fine when there are no previous versions installed, i.e. it's a new installation. Following is a screen shot of the project folder created on previous version installation: Initially the web.config file is copied in a temp folder and renamed with extension ".old" and deleted from the main project folder, screenshot below. Project folder during the installation process: The problem is that while the upgrade process is in progress the installer tries to find the new web.config file (which should've been created in the folder as the progress happens) and when it doesn't find it in the said location, the process is terminated leaving only few or sometimes no new files/folders to be created in the local project folder: Error popup window: Installation completed successfully, even though it had errors.   Any help would be greatly appreciated. Thank you Sagarica ... View more