lucy24 - 3:04 am on Oct 12, 2011 (gmt 0)
The only images that do not appear are the ones stored on the host's server.
Whoops! Do you mean your host or the school's host? That is: is it your own images or the hotlinked ones that sometimes don't show up?
:: vaguely scenting the glimmer of an explanation lurking just over the horizon ::