Update, 03/02
We have an update for you in regards to the Darkmoon Faire Achievement Progress. Please check out the following thread for more information: http://eu.battle.net/wow/en/forum/topic/3313133019#1

Update, 10/01

We’ve identified a number of issues with the Darkmoon Faire this month, and they should be resolved for the February faire. Specifically, we found problems with:

Attempting to turn in the Adventurer's Journal and Captured Insignia which are associated with these quests “The Captured Journal” and “The Enemy's Insignia”. If you are having difficulty turning in these items, please contact our customer service department at http://eu.battle.net/support/en/ and they will be able to provide you with 5 Darkmoon Prize Tickets per item.

Unfortunately, “The Darkmoon Faire” quest cannot be made available for characters that previously completed the quest. This is due to the fact that this quest is not a new quest, but reuses the old quest ID. We realize this was an error and will be taking steps to not repeat it for future quests, but it does mean that characters that completed it before will not be able to complete the new version with the ticket reward.

The reset of monthly achievement progress experienced by some is unfortunately unable to be reinstated. We apologize for this error and have taken steps to ensure it does not occur again.

January's Darkmoon Faire will come to a conclusion on Saturday, Jan. 7 at midnight. The faire will return again on Feb. 5, as planned.

We apologize for the inconveniences some players have encountered with these issues. Thank you for your patience and feedback.

Update, 04/01

A hotfix was deployed last night in order to solve the issue and the monthly quests should now be available again. However, if your character had already encountered a bug with some of the monthly quests, then you will need to wait until the next Darkmoon Faire starting on February 5 in order to complete those quests and the related achievements.

Once again we apologise for any inconvenience this issue may have caused.

Original message

We are aware of issues affecting the Darkmoon Faire which opened again in Azeroth today, particularly regarding the monthly quests and some related achievements.

Our teams are investigating the issue and would like to assure you that we are working hard to solve the issue.

We apologise for any inconvenience this may be causing.

A hotfix was deployed last night in order to solve the issue and the monthly quests should now be available again. However, if your character had already encountered a bug with some of the monthly quests, then you will need to wait until the next Darkmoon Faire starting on February 5 in order to complete those quests and the related achievements.

Once again we apologise for any inconvenience this issue may have caused.

We’ve identified a number of issues with the Darkmoon Faire this month, and they should be resolved for the February faire. Specifically, we found problems with:

Attempting to turn in the Adventurer's Journal and Captured Insignia which are associated with these quests “The Captured Journal” and “The Enemy's Insignia”. If you are having difficulty turning in these items, please contact our customer service department at http://eu.battle.net/support/en/ and they will be able to provide you with 5 Darkmoon Prize Tickets per item.

Unfortunately, “The Darkmoon Faire” quest cannot be made available for characters that previously completed the quest. This is due to the fact that this quest is not a new quest, but reuses the old quest ID. We realize this was an error and will be taking steps to not repeat it for future quests, but it does mean that characters that completed it before will not be able to complete the new version with the ticket reward.

The reset of monthly achievement progress experienced by some is unfortunately unable to be reinstated. We apologize for this error and have taken steps to ensure it does not occur again.

January's Darkmoon Faire will come to a conclusion on Saturday, Jan. 7 at midnight. The faire will return again on Feb. 5, as planned.

We apologize for the inconveniences some players have encountered with these issues. Thank you for your patience and feedback.

We have an update for you in regards to the Darkmoon Faire Achievement Progress. Please check out the following thread for more information: http://eu.battle.net/wow/en/forum/topic/3313133019#1