Fixes: #9453 Issue link: https://github.com/spring-projects/spring-integration/issues/9453 On a smb file upload, to detect the need for new remote directories, the remote path was checked for the local filesystem path separator. On Windows that is \\ which is never found in a smb path, so the necessary remote path was not created and the operation failed. Use the correct separator which was already available as a constant. **Auto-cherry-pick to `6.3.x` & `6.2.x`**