Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
Apple Set To Discuss iOS 7 & Mac OS X 10.9 At WWDC 2013
Apple has just announced WWDC 2013 with tickets going on sale tomorrow morning. Within the official announcement from Apple they said the following:
“We look forward to gathering at WWDC 2013 with the incredible community of iOS and OS X developers,” said Philip Schiller, Apple’s senior vice president of Worldwide Marketing. “Our developers have had the most prolific and profitable year ever, and we’re excited to show them the latest advances in software technologies and developer tools to help them create innovative new apps. We can’t wait to get new versions of iOS and OS X into their hands at WWDC.”
WWDC 2012 focused on IOS 6 and OS X Mountain Lion so it would stick to Apple’s previous patterns.
We did announce earlier this year we were expecting Apple to release iOS 7 and Mac OS X 10.9 at the same event due to having similar features.