Hi, I tried to change the file format in Grab (from PNG to JPG) following the instructions in this thread http://guides.macrumors.com/Taking_Screenshots_in_Mac_OS_X Unfortunately it didn't work + I can't save screen grabs at all any more - I am getting the message "Unable to create type string". I am on a 2010 iMac, running 10.6.5, and use Comm-Shift-4 to take screen grabs. Is there away to reverse the Terminal action, or does anyone know how to get this working again? Help needed!!!