Getting a 500 error when trying to access my Azure App Service with Mounted Storage using windows containers

Hi, I am using a windows docker container to access Azure file storage mounted to an app service however I get a 500 error, any ideas?

2021-03-29T14:55:14 Welcome, you are now connected to log-streaming service. The default timeout is 2 hours. Change the timeout with the App Setting SCM_LOGSTREAM_TIMEOUT (in seconds).

2021-03-29T14:55:18 PID[17628] Error ‘/c’ is not recognized as an internal or external command,

2021-03-29T14:55:18 PID[17628] Error operable program or batch file.

I’ve now discovered I only get the 500 error after creating my docker image, the code successfully publishes to an App Service. What would docker do to the image that would cause this?