PNG ICO ICNS MORE
Ravenna
wrong, Error, warning
Chocolate
256x256
warning, Error, exclamation
Fugue
Alert, Rss, warning
16x16
Direction, Error, warning
Pixelicious
wrong, exclamation, Error
32x32
Office
wrong, Alert, exclamation
Halloween
Photorealistic
Desktop Halloween
Celebration, tale, Game
Mixed
3D
Noiro
Alert, warning
128x128
Maps & navigation
GPS Map icons
pin, location, warning
Smooth
Absolute 32
warning
UI
Gnome Web Icons
Dialog, Gnome, warning
warning, Dialog, Gnome
48x48
Pixel
Led Icons
stop, Alert, warning
Crystal Clear
messagebox, warning