If you have connected to the web server and are unable to upload or modify any files, you have not logged into the relevant web folder.
Our Windows servers require that you specify the remote folder when connecting via FTP. Once you have connected to the folder where you have permission, you will then be able to upload, delete or modify any of the files in your web space.
FTP programs will refer to the remote folder, however the aim is the same. You will need to specify that particular folder on the web server that you are trying to connect too. Once you have done this, you will be able to manage your website files.
The remote folder is always your domain name, without the 'www'.