Yahoo 's email service was struggling Thursday with users around the globe complaining that they've had no access for most of the day.

It's not yet clear when the service started to stagger or how many of Yahoo's users have been affected. However, Yahoo confirmed on its Twitter account that there is a problem.

"We are aware that we have experienced an outage, and we are working to address the issue," tweeted @yahoo. "We appreciate your patience."

While some users seemed fairly patient about the inconvenience, some were a bit more frustrated when they took to Twitter to vent about the outage of their free email service.

"It's been a full day with no yahoo email. Error 15... and Error 17. What's up?!? @yahoo #yahoocare," tweeted @tmgoodwin.

And @christaylor_nyc tweeted, "Yahoo Mail down, again. Why do you make it so hard to love you?"