Window Installer custom actions fails, says the custom action failed even though it succeeded

I have a Visual Studio setup and deployment project that runs a couple executables after the commit custom action. The installer fails with this error: "There is a problem with this Windows Installer package. A program run as part of the setup did not finish as expected. Contact your support personnel or package vendor." even though the prog开发者_Go百科rams that were run in the custom action have succeeded in doing what they were supposed to do.

What can I do to prevent this error?

There's only one way to find out that a process 'did not finish as expected'. The process exit code is non-zero. Set by the return value of main() in a native program. Or the value passed to Environment.Exit() in a managed program. Or the errorlevel in a batch file. It is automatically set to the exception code if the main thread of the process dies.

You'll have to find out why one of these programs returns a non-zero exit code.