If you get this error...

/jamba : 'setmeasmaster' - unknown argument

This has to do with the recent Jamba Addon update to version 0.5. The old command used to tell Jamba who the "master" is was "/jamba setmeasmaster all". The new command is "/jamba-team iammaster all".

Fixing it the easy way

The easiest way to solve this problem, assuming you used the Quick Setup Wizard, is as follows:

1. Restart ISBoxer and make sure you're on the latest version (if not, it will pop up an update notification and allow you to click to update, or decline)
2. If you want to just clear your ISBoxer settings and start fresh, you can select File, Clear ISBoxer Toolkit Profile, and skip to step 6. Otherwise, continue on to step 3 instead.
3. Expand the list of Key Maps in the top pane
4. Right click "Control" key map
5. Select "Delete" and click Yes when prompted to confirm
6. Use the Quick Setup Wizard again. You don't need to create the same team, or even a similar team. Set up any World of Warcraft team and on the final page, just do not check the "No thanks" box, and the Control Key Map will be re-created with the new commands.

Fixing the Mapped Keys yourself

If you would rather update the Mapped Keys yourself, there are 3 Mapped Keys to update in the Control Key Map: Follow/JambaStrobe/JambaMaster, JambaMaster, and Follow/JambaMaster. That is, all of the ones with JambaMaster in the name. For each one, just change the line that says

jamba setmeasmaster all

to say

/jamba-team iammaster all