HTTP Error 502.5

.netcore 2.1.4的程序部署到IIS后报以下错误：

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HTTP Error 502.5 - Process Failure

Common causes of this issue:
The application process failed to start
The application process started but then stopped
The application process started but failed to listen on the configured port

Troubleshooting steps:
Check the system event log for error messages
Enable logging the application process' stdout messages
Attach a debugger to the application process and inspect

For more information visit: https://go.microsoft.com/fwlink/?LinkID=808681

解决方案，选中应用程序池-->高级设置-->加载用户配置文件设为true.

问题原因：IIS默认是不读取我们.netcore的配置文件appsettings.json,如下图命令执行donet path/application.dll时会出现错误提示：

找到对应的行发现是因为找不到对应的配置导致Object reference not set to an instance of an object.

修改应用程序池的设置后，问题解决。