I'm having issues getting to FTP via IE or Filezilla external to an SBS 2011 server. However if I use command prompt I can get through and put/get from anywhere. Access from IE on the server itself is fine. My setup is as follows: FTP Authentication is set to allow Anonymous and Allow Basic Authentication Specific AD groups (for users allowed to upload to the FTP site and access it internally) have been added to the FTP Authorization rules with read/write access Directory Browsing is enabled and set to MS-DOS Firewall support has 5500-5520 as a Data chanel port range and the external IP address of my router has been added. FTPIPv4 Address and Domain Restrictions are set to allow for unspecified clients FTPS is not in use No request filters are in use User isolation is set to User Name physical directory Ports 20,21 and 5500-5520 are allowed through all profiles on the firewall. From the server itself I can use IE and I can connect directly to the required folder. From another server on site I can connect from command prompt with no issues and upload and download from the correct folder but I cannot use IE (I get page cannot be displayed). When I try and open using Windows Explorer I get "An error occured - make sure you have permission. A connection could not be established". The computer account, users, system, network service all have full control to the root FTP folder and correct permissions for their individual sub directories. External to the site I can use command promtp FTP and upload/download with no issues. I cannot use IE (same issue as above) and Filezilla gives me 'failed to retrieve directory listing' I can't see why it would work from command prompt ftp but not IE or filezilla.