I am running version 1.4.3.1. This album has been working well for several years. It has gone through numerous upgrades with minimal issues. Last night a new album was uploaded and all the thumbnails look good. However, when you click on a thumbnail to look at a photo, you get a blank page. A View Source shows only the first 5 lines of the page header. The last line is a stylesheet link which, when clicked on, opens the stylesheet.

Does anyone have any ideas about what may be causing this issue?

Thanks

As always review your server error log. Otherwise our idea would be "something is wrong"…:-)

The issue was with the custom theme. Over time something changed. I switched to the 1.4.3.3 default theme and it works. I need to rebuild the custom theme.