''<t> Is nog a valid name'' help?

[Niwashi]

/ta is basicly the same thing as <t> then?

One changes who your current target is, while the other is for using an action on your current target.

/ta tells it to change your current target to whatever you specify. So:
/ta <2>
for example, would make you target the second player in your party list (usually the tank if you set your party list sorting up with tanks first, since party member 1 is yourself).

The <t> placeholder, on the other hand, simply says to use the specified action on your current target. So:
/ac "Raise" <t>
tells it to raise whomever you currently have targeted.

This makes the combination of:
/ta <t>
mean "change my current target to be whatever is already my current target." So, rather pointless.

I keep getting the pop up that ''<t> is not not a valid target!'' when using this macro, what is going wrong?

Back to your original question, this would come up on the "/ac Raise <t>" line if you either don't have a target, or if you're currently targeting an enemy.