It slows down the user's PC by using many system resources. It would start to change the user's browser homepage to a malicious copy of the Yahoo! webite. The program would later open up Internet Explorer to show advertisements on potentially malicious webpages. It does this as a pay-to-click scheme. It has been identified by many antivirus companies. This PUP can cause serious damage if left uncontrolled.
Check in your Task Manager to confirm if you have Yahoo! Powered, although task manager is useless for removing or stopping Yahoo! Powered. Download and run Malwarebytes and do a quick scan to delete Yahoo! Powered. Once this is done, download and run AdwCleaner and do a quick scan. You will have to restart your PC after both of these scans are done and it is very difficult for Yahoo! Powered to do permanent damage although the malware that can potentially come from it possibly can.