I'm having some difficulties with PS CS3. My problem is that, when I wish to select filters, only some are available, others are shown in gray and not available for use. The same problem occurs when I want to switch a layer to lets say, overlay, I cannot do that. It is also shown in gray, instead of the regular black color, and I'm unable to switch my layer to overlay. Is there anybody who knows how to fix this? EDIT: When I open a .psd file which I already had, I don't have this problem. In new .psd files however, this occurs.
It is your color depth I believe. If you have it set to 16 bit or higher those options will not be available. Change to 8 bit and see if that problem goes away. If it does then that was it.