On the evening of April 10th, there are difficulties in Battle.Net (Blizzard App), leading to login issues for Diablo 3, Overwatch, WoW, and other games. Players cannot log in and are facing closed doors. The server status at WoW is experiencing problems. Hearthstone is down.
For a few minutes now, there have been issues with Blizzard’s servers. The service of the Blizzard App, which connects players with Battle.Net, is affected. Apparently, players cannot log in.
Server Status – Diablo 3, WoW, Hearthstone, Overwatch, HotS down
Players in WoW, Hearthstone, Overwatch, Diablo 3, or Heroes of the Storm are currently complaining about login issues. They occurred around 8 PM on Monday evening, which is prime time. Error messages like Blz51903003 or Blz51900073 are being looked for.
Blizzard has already stated that the issues are known, preventing users from starting and playing games. Blizzard is working to resolve these problems as quickly as possible.

Also via Blizzard Twitter comes the news that they are working on the issues. It seems to be related to the authentication servers. These problems are causing slow or failed login attempts in WoW, Hearthstone, and other games.
We’re currently investigating an issue affecting our authentication servers, which may result in failed or slow login attempts. #BlizzCS
— Blizzard CS EU (@BlizzardCSEU_EN) April 10, 2017
According to initial information, it seems that not only Europe is affected, but also North America and even China are struggling with login difficulties, particularly in Hearthstone. The latest expansion “Journey to Un’Goro” is live, and the desire to play Hearthstone is correspondingly high.
When will the login be back?
Update 8:50 PM: Not good news. Blizzard has commented again on Twitter. They are still working on a solution and will provide another update an hour later. It sounds like the login issues may persist for a while.
We apologise again for the inconvenience caused by today’s outages. We’re working on a solution. More updates in an hour. @BlizzardCSEU_EN
— Blizzard CS EU (@BlizzardCSEU_EN) April 10, 2017
Update 10:56 PM: Blizzard has resolved the issues. You should be able to log back into WoW, Overwatch, Hearthstone, and the other games.
The technical issues we were experiencing earlier have been resolved. We apologise for any inconvenience caused. #BlizzCS
— Blizzard CS EU (@BlizzardCSEU_EN) April 10, 2017
You can see all 135 cards of the new expansion for Hearthstone here.