launching error with opengl tag, not without?

[tparker <tparker@xxxxxxxxxxxxxx>]

If I add the -opengl tag to the launching command for WoW I get a pop up 
box that says:

"Launcher requires permission to the World of Warcraft Registry key to 
successfully locate and run the game. Please enable write access to the 
Registry key using an administrator account."

I regularly switch the game between opengl and d3d and have never seen 
this before today. I do not get it without the -opengl tag. Can anyone 
point me in a direction for the problem? I didn't find anything on the 
appdb that looks wrong for my system.