This has been bothering me for a while too. I have been wondering whether it was a copermine problem or not, because once it happens, it affects all images that try to load in that window, whether in coppermine or not. In other words, if the lockup occurs, I can't see images in any website I surf to using that window, whether it be google, yahoo or whatever. This is with IE6 on WINXP, on mozilla there is no such problem, however 95% of my users use IE6.
Indeed it does seem to happen at random, EXCEPT for one single user album, which I have found to cause lockups EVERY SINGLE TIME I open the album. To try it yourself, go to the following url, and then try to open any other website using that window. I can assure you no images will show up (OK, at least they don't on my computer, or any computer near me right now).
Hold Shift while clicking to open in new window:
http://photo.enctu.org/czarYou will notice that many of the pictures in this album already do not show up, even though the files ARE on the server. I know they are there because I checked, and they are physically there, and they are accessible if you type the direct URLs to the images.
Coppermine IS doing something to the browser, that is disabling it from displaying images. I am utterly clueless what may be causing this, because from the source file, I see nothing different from other pages.
Owens, I assume this is the same kind of problem you are having?