If an installer class action throws an exception, Windows Installer will stop your install with error 2869. This is the normal behavior. So if your custom action encounters a problem, you should try to handle it silently and exit gracefully (return value 0).
For your custom action I can offer only two suggestions:
•replace the exception throwing with something that handles the problem silently
•debug your custom action to see what exactly happens when it fails
你的程序包写了自定义的代码进行操作了吗?