How do you overcome connection closed error message while installation of Qt creator using online installer?

[Meleke]

I'm completely beginner to the Qt creator. I've downloaded the following files
1st: qt-creator-opensource-windows-x86_64-14.0.1.exe
2nd: qt-online-installer-windows-x64-4.8.0.exe

I tried the first one, but I seems just Qt creator IDE gets installed with no libraries, or some features that are required for the GUI development.

Then, I tried the second file. All steps of installation work smoothly but problem comes at "installing" section where my installation stays around 4% for bunch of hours. And then I get this error message of connection closed. See the attached SS for this.
I also have tried other links for its installation available here: https://download.qt.io/online/qtsdkrepository/windows_x86/root/qt/Updates.xml.mirrorlist
But It also didn't work.

Hope I'm able to convey my problem effectively. :)
How can I overcome this problem, any suggestion will be great help :)

[Axel Spoerl]

Select another mirror.