QWSSocket::connectToLocalFile could not connect:: Connection refused

[anda_skoa]

if i go to Qt creator Help-->About Qt Creator option it is telling that "Qt Creator 3.4.2 (opensource) Based on Qt 5.5.0 (GCC 4.9.1 20140922 (Red Hat 4.9.1-10), 64 bit) ) , So is this Qt version of 5 or 3

Which part of Based on Qt 5.5.0 is confusing?

Also there is not version of QtCreator based on Qt3.

Cheers,
_