Hi,

I have create a test application which connects to a Server on local host. If I execute the test application with Qt 5.8.0 the following code fails with AbstractSocket::ConnectionRefusedError.

m_pSocket = new QTcpSocket(this);
m_pSocket->connectToHost(host, 31234);
bool bRet = m_pSocket->waitForConnected();

In Qt5.7.1 and previous versions(5.5 and 5.6) the same code works fine.

The Attachment contains a Unittest project.