Professor Portmatt's Lab Bug
You may find these articles helpful:
http://wiki.guildwars2.com/wiki/Talk:Professor_Portmatt%27s_Lab#Broken.3F
http://wiki.guildwars2.com/wiki/Professor_Portmatt%27s_Lab#Walkthrough
Good luck.
I checked those, but they didn’t help. I know what I’m supposed to do, but the thing i need to interact with can’t be used.
Have you tried guesting to another Server? Sometimes events that are stalled or items inoperative act differently at another IP. Worth a try. =)
Good luck.