Yellow exclamation by subsystem item installed on ship.

[DiamondDuty]

What does it mean? It does not elaborate on what the issue is.
It is an X5TN-III FOR +10 armed slots and +6 auto slots that has the yellow exclamation on it.

I also have another turret slot which gives another 4 armed, 1 defense and 3 auto.

My ship currently has 11 armed and 3 defense, + torpedos. But those aren't turrets anyways.
Yet I have a yellow turret icon telling me I don't have enough slots for my turrets.

What is going on?

Edit: I needed more arbitrary turret slots I guess.

[G.C._madGin]

I get the yellow turret warning issue whenever I dock a ship onto the one I am currently piloting. All the turrets seem to work fine though so I have no idea what that is about.

[Iteration: Al Terra]

Yeah, I've noticed that with my super high powered coaxials on Tree Cafe 1. I definitely have enough turret slots and all my guns are firing however I get this weird warning.

[M]

The (!) mark on things means it's a mission item and selling / trashing it is probably not a good idea. Mousing over the ! mark will bring up a tooltip that says as much.