This is my current understanding of how this should be done: (TL;DR for the actual problem, please see the bold text.)
- Create a folder on you storage server, henceforth known as B.
- Create a local user account on B, henceforth known as BUser
- Share that folder
- In folder properties>sharing>advanced sharing>permissions, add BUser and give full control
- In folder properties>security>Edit... , add BUser and give full control
- Create a local user account with same name/password on your web server, henceforth known as A
- In IIS settings, navigate to the node under which you want to create virtual directory
- Right-click > Add Virtual Directory... --In Alias, put the name that you want the directory to appear as
- In Physical Path, put: \B\shared-dir
- Click Connect As...
- Enter the username and password of the local account(s) that you created earlier.
- Click Test Settings...
- Green check icons on both items indicate that your share is accessible and fine.
- Right-click the virtual directory > Explore - Get error, either: "the specified network password is not correct." - Or: "Logon Failure: Unknown username or bad password."
It appears that the errors above are selected at random, but the second one seems to be a bit more common when trying the last step multiple times. I am totally stumped as to why. Any ideas?