Hello,

So fatjuicymole, you were right. moveToThread(this) + qRegisterMetatype() in the ctor solved the problem. And qRegisterMetaType() was required only because, in part of the code I had cut out in order to make the example more compact for posting, I emitted a signal (via another function call) which contained a string argument. Running it with that commented out produced no warning. Now I have a problem whereby sent messages pile up in the 'client' process unless I put in a 20ms pause in between each one, but that looks like a separate issue. Thanks so much, I think this would have taken me quite awhile without your help--moveToThread() is not referenced in the QThread documentation.

Matt