can anyone help me please !!
To quote the UE4 installation trouble shooting guide. (Which is found here:A new, community-hosted Unreal Engine Wiki - Announcements - Epic Developer Community Forums)
These errors are typically due to a conflict with the existing Visual Studio 2015 redistributable components on your system. To try to resolve this, navigate to the Windows Uninstall Program in the Control Panel and uninstall the Microsoft Visual C++ 2015 Redistributables. Afterwards, run the UE4 installer from the Epic Games Launcher to reinstall the redistributables.
There is another thing that may be causing these errors: The administrator access request popup window. If you ignore/not see this or press no, the installation is going to hang.
Hope this helps, and do remember.
That if you have a problem, try reporting it to the Answerhub! 