cant expand appearance in illustrator

Sometimes saving a copy to the earliest Illustrator version compatibility may be another option.

I would go with Jacobs suggestion, also depending what exactly you are after you can fill and stack layers accordingly.

Here's the solution. Get the brush tool, then set the Brush Definition to charcoal. And now brush just a small line anywhere on your canvas not overlapping your current design. After that select all then Expand Appearance will be available. It is important to not set the brush definition to basic, setting it to charcoal or anything but not basic will work.

It turns out that expand appearance is only available to complex brushes or strokes.

Hope this helps.

herms_ra,

I am afraid this is not something for Expand (Appearance).

Presuming you have closed individual paths, you may select the relevant ones and Pathfinder>Divide, then delete the unwanted ones.

Or you may click on the paths you wish cut parts off, then cut with the Scissors Tool and delete the newly cut unwanted paths. Smart guides are your friends, telling you when you are there (saying intersect where the paths cross).