Here's what we've learned about the issue. It occurs when SDF SuiteApp deployments fail unexpectedly with the message

Access to folder path 'Web Site Hosting Files' was denied.

under certain circumstances. Those circumstances are when the Host HTML Files feature is enabled in the account to which you are deploying but the role you are deploying with does not have the Website (External) publisher permission. There are a couple of workarounds: 1. We recommend you use the first workaround. Simply assign Website (External) publisher permission to the role you are using for deployments. This permission can be found under the Lists tab when assigning permissions to a role. 2. Alternatively you can disable the Host HTML Files feature in the account you are deploying to. It can be found under the Web Presence tab on the features page. Additionally, you might find that when using the SDF CLI to deploy a SuiteApp you are running into the same error message even if the Host HTML Files feature is disabled in the account you are deploying to. In that case, please provide the CLI deploy command with the

-no_preview

parameter which should resolve the issue for you.