Hi @Christoph  As per windows error look up the error says the password is incorrect, since you are sure its correct password , try to sign your setup.exe using signtool and verify it signs successfully outside of installshield. https://learn.microsoft.com/en-us/dotnet/framework/tools/signtool-exe Are you facing the issue with only 2 dll's (Hardcodet.Wpf.TaskbarNotification.dll, CommonInstaller_dl.dll", ),if yes, then remove this dll's and then try signing and check signing works or If you selected sign files in packages option YES under signing tab, remove that option(meaning set it to NO) and verifying it sign the setup.exe Also try a sample project with your certificate and verify it works or not. and try to add this dll (Hardcodet.Wpf.TaskbarNotification.dll, CommonInstaller_dl.dll) in your sample and again try to build and verify it works or not,  You can also create a new support with active maintenance,  So Could you please navigate to Get Support > Open New Case in the top menu and open a new case to track this issue if you would like to proceed with having this issue addressed? That will allow us to best track this issue in order to best assist you.  ... View more

Greetings! After checking/updating the UseAPIRegistryHooks  to use the 2 value we are no longer seeing the issue! In a bit of curious note, after cleaing registy andinstalling InstallShieild2016SP2StandaloneBuild.exe on a Windows 10 machine the value of UseAPIRegistryHooks was set to 1 not 2. Either way we found our problem and are able to move forward. Thanks very much for the suggestion! -Chris ... View more