Both of them. It happens when it tries to duplicate the "background" layer and use lens correction.
When I edit my images, I always unlock the image so it changes the name of the layer from Background to something like layer 0. So I tried to rename the layer back to "Background" and lock it and tried the actions again.
It goes through each action and then when it gets to "Duplicate Background", a pop up comes up saying "The object "Background" is currently not available." and the same goes for lens correction, "The command Lens Correction is not available."
I don't know, it could be something I'm doing wrong.
It works when I open a new image. I think it probably has to do with the format of my photos, since I import them from my DSLR. I'll try to figure it out. Thanks for the actions though ! Sorry for the trouble.