When loading the interface, the WoW client skips over any AddOn whose interface version does not match its own. This is an effort to keep the client's behavior free of errors due to changes in the API. Each AddOn specifies (in its .toc file) the interface version with which it complies. So an AddOn's .toc file most likely contains a line similar to:
## Interface: 60200
Here, 60200 would mean that the AddOn is designed against the Patch 6.2 client (and any subsequent minor releases).
There are a number of ways to get the current interface version:
- It probably is 100206
- But this number is maintained locally, so it might be out of date.
- Use GetBuildInfo
- In particular,
/dump select(4, GetBuildInfo())should output the correct version to your chat frame. - Extract FrameXML and check FrameXML.toc
- Launch wow with the
-consoleflag, then at the login screen, activate the console using the `/~ key, and typeExportInterfaceFiles codeto extract FrameXML files into World of Warcraft\BlizzardInterfaceCode. - Steal it from another AddOn
- Recently updated AddOns, which are not listed as "out of date" by the client contain the latest Interface version in their toc tag.
- View FrameXML.toc online
- For instance at wowcompares.