Windows is blocking random websites

My gf is running Windows and some time after she got Windows 8 some DNS issue occurred and random webpages started to get blocked. After update to Windows 10 this problem was still ongoing. To "fix" this she had to use

ipconfig /flushdns

But that was just a temporary fix because later same day you could need to do this again.
I did multiple web searches and in the end I found this method that seems to fix this issue.

Run CMD as admininstrator.
In the command line type:

netsh winsock reset

Press Enter then restart your PC.

Netsh winsock reset is a helpful command that you can use in Windows to reset the winsock catalog back to default setting or clean state.
In computing, the Windows Sockets API (WSA), later shortened to Winsock, is a technical specification that defines how Windows network software should access network services, especially TCP/IP.