How to connect to a server that does not allow an access to the root path?
With HTTP-based servers (WebDAV or S3), it is possible that the server does not allow an access to the URL root path, like https://www.example.com/.
With WebDAV, the server often runs on a subfolder, like https://www.example.com/dav/. Accessing a folder outside of the WebDAV root will often result in a error message “405 Method Not Allowed”.
With S3, your credentials may disallow an access to a bucket list, which WinSCP otherwise presents as a root.
In these cases, you have to configure WinSCP to start in the subfolder straight away.
GUI
In GUI, you do that by filling the path (e.g. /dav or /bucketname) to Remote directory box on Directories page of Advanced Site Settings dialog. Particularly with WebDAV, a handy shortcut is to paste a full URL (https://www.example.com/dav/) on Login dialog. WinSCP will parse the path out of the URL automatically.
Scripting
In scripting, specify the path directly in session URL in open command:
open davs://www.example.com/dav/
.NET assembly
In .NET assembly, use SessionOptions.RootPath:
C# example:
SessionOptions sessionOptions = new SessionOptions { Protocol = Protocol.Webdav, HostName = "www.example.com", RootPath = "/dav", ... };
Generated Script/Code
Note that even if you have the script or code generated from a working WinSCP GUI session, it won’t include the root path, as the GUI cannot be aware of the root path restriction.