March 12, 2011, 8:47 a.m.
posted by lordnikon
Layer comps are snapshots of all the layers and their attributes. If one layer (or more) is merged into another layer, deleted, or converted into a Background layer, a tiny warning icon appears in the Layer Comps palette next to the layer comps that are affected, as shown in Figure.
You can do a few things in this situation:
Ignore the warning icon altogether. If you do this, you might lose some layers that are important to you.
Use the History palette to activate a history state before any layer deletion, merging, or conversion. (For more about the History palette, turn to Technique 25.)
Right-click/Control+click the warning icon to view a menu that lets you choose Clear Layer Comp Warning or Clear All Layer Comp Warnings.
Click the Update button at the bottom of the Layer Comps palette to make the layer comp current.
Delete the layer comp with the problem.