Using NAM for uploading files to any online server with POST method will fail in Qt 4.6.x and Qt 4.7.x because NAM loads the binary file completely into a buffer located in random access memory.
Issue occurs only when file is larger in size than available memory at the moment. NAM build and sends the request only when complete binary is loaded in memory buffer using memcpy. Works fine for files smaller in size then free RAM.
This has been fixed in Qt5, I'm requesting a backport to Qt 4.8.
Point of order number 1, last paragraph.
At current state, developers are forced to disassemble the POST request and send it in sequential chunks via QTcpSocket which does work fine but requires signals interconnecting and is highly unstable in case of connection loss.