Rebex SFTP implements SFTP v3 and v4. In both of these versions, Unix-line paths with forward slashes and a single root at "/" is to be used:
This protocol represents file names as strings. File
names are assumed to use the slash ('/') character as
a directory separator.
File names starting with a slash are "absolute", and
are relative to the root of the file system. Names
starting with any other character are relative to the
user's default directory (home directory).
Some Windows-based servers accept backslashes as well, but relying on that behavior is strongly discouraged (and not needed because forward slashes work as well).