Ive been testing and it doesnt work I think? Could you please post here your xml? When you write 12.000, does it works? Yes, the xml shows it because now it is read only but does the game shows 12000 for real?
Atmoran - Barbarian
"I'm descendant of Ysgramor.I came from the ancient lands of Atmora."
Don't write 12.000, but 12000 as the max value for ViewDistance in MainPrefs.xml. Either use Aoc quickstart or edit it just before you press Start in launcher.
The game shows 12000 for real, but as I said "only from you log in the first time till you zone or change character". After that it defaults back to 2048 even though /setoption ViewDistance still says it is 12000. And it won't go above that till you restart the client, so it is kinda pointless beyond proving that the game runs fine at a very high view distance. It is the devs that needs to change it so the dreamworld engine dosen't default back to 2048.