Is there a way to run a docker command on docker for windows to give permissions to a container folder for a user (IIS)

I have not been able to find a working solution (or at least for me) and have found some posts explaining that there may be something coming down the pipeline.

In a nutshell I have a ASP.Net 4.6 web app and it is running on docker, pointing to SQL and all the usual stuff. I now need to save files to the docker container as part of the web app. (files uploaded by companies that use the app). For this to happen, I understand I need to allow the IIS user access to a directory on the docker container.

If anyone has solved for this please let me know. (or if you have other solutions for this scenario, that would also be most welcome.)

Happy 2021!

Cheers,
Marc