Hello,

I'm using 1.1 and the printCustomSizedImage for the images in the theme. When I validate, I get this message and an invalid page:

cannot generate system identifier for general entity "i".

….php?a=residential%2Fprince-george-1&i=12.jpg&s=650" rel="lightbox[Residence]

Now, when I refresh the page a few times and click on all the images, then I get a valid page.

What's up with this?

bump

You don't have mod_rewrite set. These are the (perfectly legitimate) kinds of links that zenphoto uses when it is not allowed to create cruft-free URLs.

I do have mod rewrite on in the admin settings and the .htaccess is also working fine.

You will have, then, to upgrade to zenphoto 1.1.5.

The validation problem is in the URL. It should be:
....php?a=residential%2Fprince-george-1&i=12.jpg&s=650" rel="lightbox[Residence]
to validate correctly.

ZenPhoto uses the non-validating "&" instead of "&" in a number of places. If it's a URL inside HTML, it should be "&". On my site I've already cleaned up the RSS feed links.

True...we will work on that (we probably don't notice it that clearly since we basically always use modrewrite).

Actually, the url is correct as it stands it is a 'query' url passing the parameters a, i, and s to the i.php script. Changing it to & may allow it to validate but it will not work within zenphoto.

No, that's wrong, it is not valid syntax, ampersands in query strings as part of in-page markup need to be escaped:
http://validator.w3.org/docs/help.html#faq-ampersand
http://htmlhelp.com/tools/validator/problems.html#amp
The browser will correctly unescape it, so it should work fine.

It's a very common error, but it will cause W3C validation to fail.

As do many hacks to get certain "unbrowsers" to show sites correctly. But generally you are of course right.