It's one of the most popular sites in the world, but it looks like Yahoo has crashed this morning.
According to DownDetector, the problems started around 07:38 BST, affecting users worldwide.  Although the cause of the power outage is still unclear, 61% of those who reported problems about the site said, while 38% struggled to sign in.
Yahoo tweeted about the problem 40 minutes ago and wrote: "You may not have access to any of our services, including email. Our top priority right now is to fix this. We appreciate your patience. "
Several people have taken to Twitter to vent frustration this morning.
One user tweeted: "Server down on day one of the football season …"
Another added: "This is so annoying ̵
? Your entire network is down. You lose your customers money … including me. Incredible. "
Mirror Online has contacted Yahoo for comment.