When I take the portal from Dorn to the Timeways and then to Maldraxxus I automatically get dismounted where it drops you off. When I try to mount again it just automatically dismounts me. So then I have to jump off the pillar it leaves you at and run far away from the theater of pain area. Eventually i can mount. When I fly over to where the portal should be there is no portal for the ToP.
Sometimes very very briefly (1 second) the portal appears and people waiting for their groups appear. But then I get sent back to my own instance.
Has anyone had this problem? It has made ToP impossible for me, because I literally cannot enter the instance.
Edit: Jeysca was right, i had to do the main quest of maldraxxus. Just a few quests until i got out of the ToP zone. Now everything works!