WoW key combinations, why do some not work

Alright, I've read through lots of post regarding mapping and combinations but can't find an answer to this...
Why do some key combinations in WoW not work?

for example, when I press Y in WOW, this gives me the achievement window.
I have a wow named macro "A", with a key combination CTRL+SHIFT+ALT+Y which executes macro a --> works fine.

when I press U in WOW, this gives me the reputation window.
but when I use the key combination CTRL+SHIFT+ALT+U, that same reputation window keeps popping up.

in WOW, P = spellbook, yet a macro with key combination of CTRL+SHIFT+ALT+P does nothing, macro doesn't execute, but spellbook doesn't popup either.

so, why do some combinations work and others not and how am I supposed to know which are good to use besides trial and error?

Thanks,
Kokky

[lax]

I think you have misunderstood the problem.

When you are setting up WoW macros through ISBoxer, they are installed via the ISBoxer Addon. This Addon is created when you "Export to Inner Space".

Now.. if you do this while playing the game, the ISBoxer Addon on the disk is going to be updated, but WoW still has the old one -- with the old macros -- loaded. If you make changes to WoW macros through ISBoxer while playing, you will need to /console reloadui after Exporting in order to force the Addon to re-load and install the new macros. (Or alternatively, camping out to Character Selection accomplishes the same thing).

If you ARE making sure the new one is loaded by both Exporting and reloading the ISBoxer Addon, then it is more likely that this WoW macro is not assigned to this Character through ISBoxer:
* If you're using the WoW Macro Library (recommended) you can click on the WoW Macro Set to make sure that the Character Set or Character is highlighted that you expect the macro to work on.
* If you're instead using a WoW Macro Action (not so recommended) then you will need to ensure that the Key Map that contains the Mapped Key with the macro is assigned to the Character Set or Character, and that the Target of the WoW Macro Action is set to include the correct Character. (If I just confused you, this is a good reason to use the WoW Macro Library and Named WoW Macro Actions instead of WoW Macro Actions)

Ctrl+Shift+Alt+Y U and P are no different from each other as far as being able to set up macros. Hope this helps.

So, I just came home, loaded up innerspace, got my config from dropbox, exported it and started my team.
Tried the macro's, and they ALL work, all those buttons which I've configured.
The pc on which I've been testing this afternoon is still at work so I'll try on that one tomorrow.

I always do a /console reloadui, after every single change I make, just to be safe.
I've been setting up according to the "setup ISBoxer like a pro" wiki, which is awesome btw, and gone over everything a few times.
Only use the named actions and the char was definitely highlighted.

Ah well, it's working now, I'll let you know if it works on the other computer in the morning!

....aaaaaand it works here as well