High population servers are currently experiencing issues preventing players from logging into the game and Blizzard is working to resolve the issue as quickly as possible. Some players have not received their Heart of Azeroth according to latest reports.
Update: Blizzard is still trying to come up with a solution for both problems. Tichondrius will be restarted soon.
We’re continuing to work on a solution for ongoing login issues and we’re working to address this as quickly as possible. Tichondrius will be undergoing a rolling restart to test some changes shortly.
Affected realms include Area 52, Illidan, Tichondrius in North America as well as Draenor & Hyjal in Europe.
At this time, we are aware of and working to resolve an issue that is causing some players to be prevented from logging into certain high population realms. While it appears that not all high population realms are affected, the issue seems to be affecting realms such as US-Area 52, US-Illidan, US-Tichondrius, EU-Draenor, and EU-Hyjal.
This is an issue of highest priority for us, and we are working to resolve it as quickly as possible.