Laki, we need way more info to be able to help you: what action, what version of Photoshop, did you read the readme that is often bundled with the action. It may require a text layer, an image layer, to be run on the Bg layer, etc…
Check the mode of your image 8bit, RGB?
Its Photoshop 7,0 and thers no readme document. It is 8 bit and RGB.
You can’t count on actions that you download to have been written properly. Case in point, "Layer Style not available" most likely means that either there was a custom layer style that wasn’t included, or it uses a photoshop default layer style that you don’t have loaded.
You have to watch the action and pick it apart step by step – and that’s not always successful when someone else wrote an action and you aren’t sure where they’re going with a particular step.
Peace,
Tony