Used ccleaner basic clean up (registry and file clean up) on W8.1 pc and now i have problems browsing. Findng a host is extremely slow. For ie but also Chrome. I gues dns cache is flushed/removed so it could take a bit longer but not his long. What to check, any suggestions? All appl are up to date and no infections as far as i know.
It would only clean DNS Cache if you enabled it to do so, I think the cleaner for it is off by default.
Perhaps rebooting, or unplug then plugin the electrical power for your modem could solve the issue - well that's what many ISP's will tell people to do first.
If you suspect it's DNS related perhaps go into the Windows services and make sure DNS Client is enabled and running (or restart it if it is already running). One caveat though is if you use a big HOSTS file like that from MVPS.org, etc., they either recommend or automatically turn off the DNS Client because with a large HOSTS file having it enabled and on can significantly slow down your Internet connection.