So I'm aware with the WotLK client crashing due to memory being insufficient. The work around was using an external software of sort to enable WoW.exe to use more than 2gb of memory. I did that, and I am still crashing in dalaran. I looked at multiple guides, read them meticulously, and followed them. So what am I doing wrong?
Hmm, tough question.
There's something that may work tho!
Have you tried downloading more RAM?
Give http://downloadmoreram.com/ a try.
It allowed me to upgrade from 4 grags of ram to 8, maybe it works for you too. :)