I have been googling this issue for days now and I cannot find a answer to my problem.

My issue is I am running KDE on a 3k resolution monitor so all my fonts are very tiny, in my KDE settings I have changed the font size to 20 on all apps and forced dpi of 96, this works fine for most applications.

However when I run certain apps like "WICD" or "Ettercap" etc the font reverts back to normal size and is very small and hard to read is there anyway I can force every application to use the same font size that KDE is using?

The resolution is probably still wrong (actuall 96dpi should be X11 default) -> fix that to the proper size (if you need help on that, please post the output of "xrandr -q") and "normal" font sizes should be or proper size.
some applications like eg. firefox will likely require additional settings (about:config)

ettercap and WICD are gtk+ applications; you'll need the gtk+ systemsettings module or some gtk+ theme editor like gtk-chtheme to alter its font settings (or edit the resp. ~/.gtk* files by hand)

Thank you very much installing GTK-Ctheme worked a charm just boosted all the fonts.

As for my resolution I know its not working it wont detect my display so I gave up that route and just boosted all my fonts