This is a very old issue.
by R. Proffitt - 2/17/12 3:37 PM
In Reply to: Moving from IPhoto to Craigslist Different than other post by nanccn
I'll start with http://forums.macrumors.com/showthread.php?t=451744
Most photos are far too big today for craigslist so give yourself time to learn about external hosting (I use photobucket) or how to export and resize such (read link).