Been a while since I last posted here.
I am using the xsi mod tool.
I am learning to character model.
In character modeling it is a must to use symmetry. I have tried a lot of suggested methods and got it to work, but it always seems to break somewhere.
I will be working along then not all the verts are symmetrical, usually just one or two.

never mind figured it out.

ok well thought I had it "Wrong".

Make half an object.
Freeze its Translation and scaling.
Put object under a model.
Instance the model.
Scale it at -1 on the desired symmetry direction (usually x).

That is what I did ,but the center verts will move in x. earlier when I followed this method they did not.

Is there something I am missing?
Help please

That workflow looks correct... I use a clone instead of instancing a model though (I just think it is simpler). Like this:

1. Make sure your center vertices are at 0 in x (or desired axis). You can just select them, scale them Globaly (without COG) and press CTRL for Scale snapping... Scale until reaching and snapping to 0.
2. Freeze your transforms and delete half of your mesh.
3. Clone (not duplicate) it.
4. Scale -1 in x (or desired axis).
5. Keep modeling until you feel happy...