WoW was unable to start up 3D acceleration

[Briano]

WoW was unable to start up 3D acceleration. Please make sure DirectX 9.0c is installed and drivers are up to date.

I have drivers up to date and DirectX installed.

WoW 4.3.4 / WoWMoP / and WoW 6.2.3(retail) all work fine. However 3.3.5 does not and I get the above error. I have restarted my computer and reinstalled my drivers. It use to work fine

[skullatbash]

It use to work fine

you meant " it used to work fine"
OR you mean now it work fine, so basically you have already fixed it?
In case you haven't fixed try to get a new Wotlk client from here: https://www.warmane.com/download
I recommend "Wrath of the Lich King (old)"
obviously you can copy paste your old Interface/WTF