Our website is http://www.bostonknitting.com/ Twice in the last couple of months the main part of all the pages has just disappeared. All that was visible was the header area. No one had made any changes to the site.

Once I managed to fix it by applying a backup of the entire site. This most recent time (yesterday) I applied all the updates available to the Atahualpa theme 3.7.3. I was already at WorPress 3.3.1. Everything seems to work now, but I'd like to get to the bottom of why this happens.

Thanks!

You need to investigate it without fixing. You should look at the logs of the site and recall if you had done anything - and I mean anything like add a post, change a parameter, add a widget - just before the error happens.

You should contact the host and see what support they can give you.
Try swapping themem, disabling all plugins.

This is all gathering information that could leave to a solution. Maybe you are running out of memory or the post you added had some code that causes and error.

Sorry that is about the best advice I can give you at the moment.

Thanks. I've checked logs and didn't find any clues. I will continue to do what research I can.