I have a 500MHZ TiBook that I just installed Panther on about two weeks ago. Ever since the upgrade none of the .dmg files have opened. I get the same error: error - 536870208 When I get info on the .dmg file it says the file DiskImageMounter is the default application to open with. Any help is appreciated in advance. Eric Krosnes Systems/Network Administrator Evansville Courier & Press Evansville, IN 47713