Continuity mistake: It was briefly stated in the second film that the T-Virus was created by Dr. Ashford to cure his daughter Angela and that the Red and White Queens were based on her. This movie contradicts that by suggesting that Dr. Marcus created the T-Virus to cure his daughter Alicia, and that the Red/White Queens were modeled after her. While the rest of the movie stays true to the continuity of the previous films, this rather obvious ret-con is still a major continuity gaff.
Continuity mistake: There is a scene of Alice being dragged by a line behind Isaacs' tank ahead of a horde of zombies. There is no other line next to running Alice. When she climbs upon the tank to attack the guard, another line with torn hands is seen being dragged on the road, where Alice was dragged. (00:21:15 - 00:23:45)Bunch Son