Chrome to Yahoo hijacker

Only in Chrome. All extensions were checked, nothing found. My son also ran diagnostics in case I missed something (he is much more computer savvy), still nothing.
I keep getting a hijack also to: nowupgrade24.perfectupdater.net - which is a dangerous site, but can't stop the popups.
 
They have been reset. Transferred bookmarks to a new setting. Ran ZEMANA Antimalware, it found a trojan and the hijacker. Still receiving a "microsoft" alert stating my computer is infected with a pornographic website. Reset safe search options, again.