My PShop 6 is acting up. For the past two hours I have bene unable to change the opacity/flow percentage on my tools and layers. It worked earlier today, but now when I go to click on the dropdown arrow, it won't open and just quickly closes again. I have updated my version and shut both the computer and PShop down numerous times. It's maddening! Any help is greatly appreciated!
If you have alread restarted the computer and Photoshop without success, and tried different images and it is still locked, then time to reset preferences. Hold down Shift Ctrl Alt (Shift Cmd Opt) imediately after opening Photoshop. Try that and get back to us.
[EDIT] I am assuming you mean CS6 and not the ver old version 6?
There are a few contexts when Opacity and Fill are not available:
1. if the layer is the background
2. if the layer is locked
3. If the layer is not visible