Anyone know how to fix this PCB layer order issue

[Psi]

Anyone know how to fix this layer order issue in altium V15 ?

Somehow altium thinks layer 2 is layer 3 and layer 3 is layer 2.  But I'm not sure the exact location where this is being incorrect redefined.

Project used to be 6layer and then became 4 layer and for some reason it wants to do a 4 layer as Top,L1,L3,Bot. Instead of Top,L1,L2,Bot.

I currently have 5 layers defined in the stackup just so I can actually edit the L2 layer since it thinks that is L3 and it disappears if I reduce stackup to a 4 layer as Top, L1, L2, Bot.

[ajb]

Been a while since I edited a stackup, can you not edit the layer name in the table view? It looks like that's the only issue, right? Or are the layer orders nor matching up in the PCB editor itself?

Alternatively, what happens if you import a good 4-layer stackup?

[asmi]

There is a checkbox in the "Properties" window of a layer named "Stack Symmetry", which might be messing you up. It did mess me up in my 10 layers stackup which was not symmetrical.

[T3sl4co1l]

Huh, first image isn't showing correctly for me (incorrect database link, file name / dimensions / thumbnail show correctly, full size image is same as second image).

Well, it should be if you move everything from layer 3 to 2, and delete layer 3, it should Just Work(TM).  Have you tried that?

Special layers are weird, layers at all really, because they are, I think, intrinsic.  You can rename and to some extent rearrange layers, but they will always have some intrinsic, internal identity and semantics.  I think the semantics used to be more rigidly fixed back in the day (PCAD or earlier?) and have gradually gotten more flexible, but it's not like it's fully general with an array of layers where any one layer can be configured to do anything.  Even in newer versions where they've expanded the possible number of layers, I think.

Tim

[Psi]

Huh, first image isn't showing correctly for me (incorrect database link, file name / dimensions / thumbnail show correctly, full size image is same as second image).

Yeah, i think the forum is having issues where multiple attachments get messed up.
The main issue is in the first image, where the name of the layer does not match the number of the layer.

What about the single one i attached to this post?

[T3sl4co1l]

Yeah, that works, and is about what I thought.

Tim

[Psi]

I've had another go at fixing this and this time it seems to have worked.

So i think all is good now.

[Doctorandus_P]

I do not know much about altium, but I'm counting 5 copper layers, and it is very unusual to have an odd number of copper layers in a design, as the production process usually only do even numbers of copper layers, so you get an extra copper layer for free.

[Psi]

I do not know much about altium, but I'm counting 5 copper layers, and it is very unusual to have an odd number of copper layers in a design, as the production process usually only do even numbers of copper layers, so you get an extra copper layer for free.

Yes, that extra layer was just me trying to fix the issue on a 4 layer pcb.
I tried adding a new layer to the design, moving everything from one of the other layers to that new layer and then deleting the old layer, to try get the layer order number to come right.

But it's all sorted now, after playing around with it for a while it came right for some reason, i deleted the 5th layer and the 4 remaining had the correct numbering.