There is a great page that covers the generic issues to may see from upgrading from IS2012 Spring which you can find here: https://docs.revenera.com/installshield23helplib/helplibrary/UpgrdngToIS2013.htm#gettingstarted_502408798_1212197 More specifically the screenshots that you have provided all complain about missing files - you should check that these files are actually present in your project so they can be built into the installer. With regards to the two .dll's , its possible that these may be file dependencies that are pulled into the installer during build time, you would need to identify which file is calling these files and also that they are available during the build process. I hope this helps, ... View more