When downloading a file via SSL (QNAM::get()), downloadProgress() and readyRead() are emitted only until a certain (seemingly random) amount of bytes have been downloaded, at which point the entire download stalls forever. No more progress or readyRead signals are emitted. Wireshark capture shows that the remote server is in fact retransmitting packets to the client after the stall happens, so this leads me to believe that Qt or OpenSSL is simply not handling the incoming data properly, and/or not sending a correct response to the server to allow more data to be received. Each file I have tested with will stall at the same three to four byte counts, except for the ~1 in 50 tries that the download is successfully completed. File sizes I have tried with range from 50k to 15MB, and I have tried multiple remote servers with different certificates and hardware/software. Non-SSL downloads work without issues.