@aha_1980 said in Problem with QTcpSocket: Hi @JCBaraza, I hope you are well aware that the waitForReady... functions can only be used in threads. If you don't have a thread (beside the main thread), you must use signals&slots, like the Fortune Client example. Hi aha1980, Thanks a lot for your quick answer. No, I'm affraid I didn't know about that. When I saw the Qt examples with sockets, I rapidly discarded using signals and slots because this kind of programming is a bit puzzling to me (just have a look to my code ;-) ). Well, I'll have to revisit Qt examples and get familiar to signals and slots outside the main window of my application. Regards,