Why can't I add a photo using AT Photo in Plone?

If you’ve used the product ATPhoto or ATPhoto Album in Plone 2.1, but now it is breaking in Plone 2.5, before you rip your hair out, here’s what you need to do:

1. copy the code from this site: http://dev.plone.org/collective/browser/ATPhoto/trunk/configure.zcml (you might need to clean it up a bit)
2. log into your server and go to your Zope folder
3. next go to /instance-home/Products/ATPhoto/configure.zcml (you might want to make a backup of this file)
4. remove the existing code and replace it with the one you’ve copied
5. restart Zope (you can do this via ZMI)

And volia! It’s fixed.