Diablo 3′s latest major patch suffered a setback on deployment but has now rolled out to prepare the game for the arrival of Reaper of Souls.
The 2.0.1 patch was rolled out earlier today but according to a forum post Blizzard encountered some “unexpected issues” resulting in a four hour extension to planned maintenance.
Later updates confirmed that the problem related to a hardware issue discovered during internal testing, which has now been resolved.
The patch began deployment on American servers and should be rolling out around the world now.
This update prepares the game for first expansion Reaper of Souls, which is due on March 25, among other fixes. Full patch notes are available here.