A couple of days ago my Internect connection began behaving strangely. At one point I had a connection on my computer but no connection on my smart TV or iPad. After some fiddling I found I had no connection on my computer but connection on the TV and iPad. This "fiddling" involved relocating ethernet cables to different ports, disconnecting and reconnecting my router, Optus modem and NBN modem. Several times i managed to get connection on everything, only to find the internet dropping out completely after a few hours. The Windows 10 troubleshooter produced an error message "Your DNS Server may not be available". I have managed to get things back to normal by doing a system restore back to a time before the problems began. Does this suggest that the problem is not related to hardware and connections but rather settings on the computer? Could it be a Windows 10 update which is causing the problem?