On Thu, 10 Nov 2011 03:31:52 AM Riccardo Roasio wrote: > there are qt classes for crypt/decrypt files using md5 or i need to > use external libraries? Use http://doc.qt.nokia.com/latest/qcryptographichash.html (QCA is another option if you really want low level crypto, but is overkill for an MD5 hash given Qt already has it). Brad