Problem solved.
Once I specified a directory access for a user, when using an FTP program there is no need to indicate the specific directory. When trying to log in I was redirected to the folder I have access to.
So, for example, if I only have access permission to a folder named:"images", I only have to provide the main URL: "
www.myserver.com", and I'll be redirected to the folder I have access permission to. In my case:"images".
Thanks,
Joel