The installation of add-ons is one of the biggest reasons people new to them do not use them. It can be scary sometimes with some of the add-ons. This will be a simple guide as to how to install an add-on for the World of Warcaft game.
Installing WoW AddOns for Dummies
The Basics :
Your [World of Warcraft] directory is where your game was installed, and where your WoW.exe program file is located. For some people this will be :
C:\ProgramFiles\World of Warcraft
For others it could be :
C:\World of Warcraft
or even
D:\WoW
It all depends on where you installed the game in the first place.
The [World of Warcraft] base game directory should contain a folder called Interface. And the Interface folder should contain a folder called AddOns So you should have a [World of Warcraft]\Interface\AddOns folder
e.g.
C:\World of Warcraft\Interface\AddOns
These folders should all exist by default, as Blizzard include some AddOn files of their own since one of the patches in 2006 - If they don't exist then you can create them (or the game itself should create them when you log in - in other words, if you have just logged out of the game, and do NOT see the \Interface\AddOns folders, then you are looking in the wrong place.
NOTE Just to be absolutely crystal clear; If you installed the game in D:\WoW, then creating another folder structure called C:\World of Warcraft\Interface\AddOns and installing AddOns there will do nothing for you. You MUST install AddOns to the D:\WoW\Interface\AddOns folder.
Installing an AddOn
Lets try and show some Examples :
EXAMPLE 1
An AddOn called "Wibbly"
This AddOn just contains 3 files :
Wibbly.toc
Wibbly.xml
Wibbly.lua
Most authors will ZIP up their files in to an archive, or use some other tool such as RAR. A few will create Executables that will self-extract (although I personally frown on this practice as un-safe). The author of Wibbly has created a Zip file with the following files AND directory structure :
\Wibbly\Wibbly.toc
\Wibbly\Wibbly.xml
\Wibbly\Wibbly.lua
You can not simply place the Zip file in the \Interface\AddOns folder - you MUST extract the above files IN their original file structure in to the \Interface\AddOns folder. So when you look in Windows Explorer, you should see the following :
[World of Warcraft]\Interface\AddOns\Wibbly\Wibbly.toc
[World of Warcraft]\Interface\AddOns\Wibbly\Wibbly.xml
[World of Warcraft]\Interface\AddOns\Wibbly\Wibbly.lua
Be careful you don't have software installed that lets you explore Zip files within Windows Explorer as if they were normal folders, which might fool you in to thinking the AddOn has been unpacked correctly; So make sure you are Un-Zipping in to the [World of Warcraft]\Interface\AddOns directory, and not just copying the Zip file.
EXAMPLE 2
Some authors will INCLUDE the \Interface\AddOns folders within their Zip files.
So for example, some author has created an AddOn called "Wobbly" in the following Zip file with the following directory structure :
\Interface\AddOns\Wobbly\Wobbly.toc
\Interface\AddOns\Wobbly\Wobbly.xml
\Interface\AddOns\Wobbly\Wobbly.lua
\Interface\AddOns\Wobbly\Graphics\WobblyIcon.blp
Because the Author has included the \Interface\AddOns folders within his archive, then the user needs to be careful to un-pack the AddOn DIRECTLY IN TO THE [World of Warcraft] directory, and NOT in to the [World of Warcraft]\Interface\AddOns directory.
(Note that in this example the author has also included sub-folders within his own AddOn directory - in this case he has specified a spearate directory to contain graphics files which are usually .blp or .tga files. You must retain this folder structure when you install an AddOn, otherwise it won't be able to find some of its files and will probably not work. For example, if you did not keep the Gaphics folder above in its correct place, then the AddOn may seem to work, but it would be unable to find the WobblyIcon.blp picture and you would probably just see a green square instead of what the author intended you to see.)
Common Mistakes of the Absolute Beginner
For example if you were do download the "Wobbly" AddOn mentioned above, then the following directory structures are WRONG :
[World of Warcraft]\Interface\AddOns\Interface\AddOns\Wobbly\Wobbly.toc, etc.
-this is wrong because the \Interface\AddOns folder included in the AddOn zip file, has been unzipped in to the \Interface\AddOns folder again.
[World of Warcraft]\Interface\AddOns\Wobbly.zip
-this is wrong because the Zip file has simply been copied in to the \Interface\AddOns folder instead of being properly un-zipped.
[World of Warcraft]\Interface\AddOns\Wobbly.toc, etc.
-this is wrong because the Wobbly AddOn files have been extracted directly in to the \Interface\AddOns folder; i.e. the Wobbly.toc file should be in a folder called \Wobbly.
NOTE : In all three cases above, the "AddOns" Button in the character Log In screen would NOT be shown, because the AddOn was not installed correctly. Only when some custom AddOns have been CORRECTLY installed does the AddOn Button show up. (The existance of the Blizzard AddOn files and the \Interface\AddOns folder will not cause the AddOn Button to be displayed on the log in screen.)
The CORRECT file & folder structure for the Wobbly AddOn is as follows :
[World of Warcraft]\Interface\AddOns\Wobbly\Wobbly.toc
[World of Warcraft]\Interface\AddOns\Wobbly\Wobbly.xml
[World of Warcraft]\Interface\AddOns\Wobbly\Wobbly.lua
[World of Warcraft]\Interface\AddOns\Wobbly\Graphics\WobblyIcon.blp