Why is it that sometimes I when I go into the Image Editor the buttons for Adjust Light and Adjust Contrast do not work?

Clicking on them does nothing.

I can crop and rotate but not those two and the buttons for black and white, gray scale and gray scale with text enhancements is also not working.

It seems that most times these are not working and I would suspect a bad install if it were not for the fact that I have been able to use those every once in a while.

Is there some file types it works on and others it does not?

Most all of our documents are black and white text but occasionally it would be helpful to darken or lighten a page that has been scanned in.

I know PhotoDocs is for capturing images from a digital camera but it does say in the manual that you can use it to reprocess tiff files after they've been imported.