First things first,
hello and welcome to the forums djj! Glad to see you're seeking help from us here at
LanCraft.
My suggestion to you, as you seem to have some problems with applying a patch update, is to reinstall the game from scratch. After you've done this make sure you let all the updates finish downloading and installing to ensure that you have the right version to actually be allowed to log on. There might be some hotfix-updates that will download themselves, like the other major updates, when you try to log in.
If this doesn't work try downloading and installing the patches yourself. Here's a link that you can use for downloading patches,
http://www.wowwiki.com/Patch_mirrors, there's also installtion tips and guides at the bottom of that page.
I hope this helped djj.
See you around
Zarx