If you are experiencing problems with an addon, there are several basic troubleshooting steps you can take before reporting the problem. Doing these things will give you more information to give the addon's author, which increases the chance the author will be able to find the source of the problem and fix it.


Step 1: Is the addon loading?

If an addon isn't loaded at all, then the problem is on your system, and not in the addon. Common reasons why an addon might not load include:

1. Is the addon installed correctly?

Some decompression software (including the one built into the Microsoft Windows operating system) add an extra layer of folders that interferes with the WoW addon system. They key file in any addon is the Table-of-Contents file, with a "toc" file extension. You can verify that an addon is installed in the right place by locating it's TOC, and by seeing that it appears in the list of addons WoW shows you from the character selection screen.

Correct:
C:\Program Files\World of Warcraft\Interface\AddOns\MyAddOn\MyAddOn.toc

Incorrect:
C:\Program Files\World of Warcraft\Interface\AddOns\MyAddOn-v1.0\MyAddOn\MyAddOn.toc

Also make sure that your decompression software preserves file paths; some addons have sub-folders inside their main folder, and if these file structures aren't preserved and all the files are dumped inside the main folder, the addon won't be able to load.

If the addon is installed correctly, but still isn't loading, try deleting it and reinstalling it from a fresh download.

If you are using Windows Vista, there are several other "incorrect installation" issues you can look into if the above don't get the addon to appear at the character selection screen. As I do not use this operating system, I can't assist you with those issues, but there are many guides all over the Internet which can. Use Google to find them.

2. Is the addon enabled correctly?

Make sure the addon is enabled at the character selection screen. Click the checkbox next to the addon until a yellow check mark appears in it. If the addon's title now appears in red, this means there is an additional condition you must meet before it can be loaded. Look to the left of the addon's title for this reason.

"Dependency disabled" means that the addon depends on another addon; you must also enable that other addon before this one can be loaded. You can see the dependency by placing the mouse cursor over the addon's title and reading the tooltip.

"Out of date" means that the addon hasn't been updated since the last major WoW patch. In most cases, this does not mean that the addon won't work. Many patches don't change anything that addons need to be updated for, so the vast majority of addons do not need to be updated for every patch. Simply check the "Load out of date addons" option at the top of the addon list. You should never alter the interface number in an addon's TOC file. Just use the in-game option that's provided for this very purpose!

3. Does the addon have a LoadManager, and is the LoadManager enabled?

The WoW addon system includes a feature by which an addon can specify another addon as it's LoadManager. Once it does this, then WoW no longer loads the addon normally, but leaves it up to the specificed LoadManager addon to load it. Common uses of this feature are to prevent some addons from loading on some classes (for example, if you're not a shaman, you don't need to load a totem timer addon), to prevent some addons from loading before they're needed (for example, if you're not in a battleground, you don't need to load a battleground timer addon), or to delay loading some addons until after you've loaded into the game world. Using a LoadManager can decrease your loading screen time and decrease the amount of memory your addons consume. However, either by design or as a flaw, if the specified LoadManager addon is installed, but not enabled, none of the addons that specify that addon as their LoadManager will ever be loaded, even if they are enabled.

A common LoadManager supported by many addons is AddonLoader. Most of my addons support it, and you can check any addon's TOC file to see if it specifies a LoadManager. If so, make sure that you either do not have the specified LoadManager installed, or that it is enabled.


Step 2: Is there an error message?

By default, the game does not show Lua (addon code) errors anymore. You can enable error display in the Blizzard Interface Options, under Help. Make sure "Display Lua Errors" is checked. Now log out, log back in, and try to reproduce the problem. When it happens, you may see a dialog box pop up on your screen containing some red error text. Write down the full text of the error, and include it in your problem report.

Alternatively, you can install BugSack or another error handling addon to give you a more detailed error message that you can simply copy and paste, instead of having to retype it yourself.

Note that if you use the Swatter error handling addon included in the Auctioneer package, please do not include the huge list of which addons you have installed, as it is not relevant in 99% of cases, and Step 2 below will more accurately pinpoint the problem in the other 1% of cases.


Step 3: Does it happen with other addons disabled?

This is important because addons can interfere with each other if they try to to do the same thing, or if they hook into Blizzard's code in unexpected ways. If the problem still happens when you log in with only the addon in question enabled, then the problem isn't caused by a conflict with another addon, and you can skip the rest of this step.

If the problem goes away, though, you'll need to do some more detective work to find out which addon is causing the conflict. The quickest way to do this is to enable half of your addons and log in. If there's no problem, disable that half, and enable the other half. Then disable half of the enabled half; if the problem goes away, re-enable those and disable the other half. Continue until you narrow it down to a single addon.


Step 4: Does it happen after you reset your settings?

Each addon saves its settings (saved variables) in a separate file. Depending on the addon, this file may be shared between all characters on your account, or there may be one for each character. If the addon's configuration is very complex, or if the addon stores a lot of data (like Auctioneer or LootLink), you probably don't want to lose your saved variables when you don't even know if they're the problem. If this is the case, you should rename the file (my preferred method is to add two dashes to the beginning of the file's name, as this retains alphabetical sorting on Windows systems and makes the file stand out). Otherwise, just delete it.

Saved variables that are shared between all characters are located in:
C:\Program Files\World of Warcraft\WTF\Account\<AccountName>\SavedVariables\<AddonName>.lua

Saved variables that are specific to one character are located in:
C:\Program Files\World of Warcraft\WTF\Account\<AccountName>\<ServerName>\<CharacterName>\SavedVariables\<AddonName>.lua


Step 5: Report the problem!

Once you've gone through the above steps, you should report the problem to the addon's author so he or she can fix it. You should always include at least the following information to help the author identify the cause of the problem:

• The error message(s), if there are any. (Step 2)
• The other addon causing the conflict, if there are any. (Step 3)
• What settings you changed from the defaults, if the problem went away when you reset them. (Step 4)
• What locale (language) and version of WoW do you play in?
• What version of the addon you are using, and where you got it. Please state the actual version number, and don't just say "latest version". By the time the addon author sees your report, the latest version may not be what you were using when you posted your report anymore.
• What you were doing when the problem happened. For example, does it happen right away when you log in, or does it happen when you target an enemy player, or does it happen when you access the addon's options?

If you don't include enough information for the addon's author to identify the problem, he or she will probably ask you for more details. Don't just file your bug report and forget about it!