Users can configure a File Blocking profiles for any type of file. However, by using a different FTP software application the file transfer still occurs and is not blocked by the firewall. Even though the file transfer has been completed successfully, the file cannot be opened and the hash value is different than that of the source file.
Cause
This occurs on certain FTP client software applications that have the option "Reconnect to download file from last offset" enabled or embedded. The firewall will block the first initial FTP file transfer but the FTP client will reconnect again because it has some bytes left to transfer. The remainder of the file will be transfered but since the first part was blocked by the firewall the file cannot be opened. This can be confirmed by checking the hash value of the files on both