Reset your permalinks to something other than what you have now and see if the error goes away. After that you can reset to your current permalinks settings.
Hi Krishna,
Just managed to try that – has no effect. The error remains. It’s very strange. The page is clearly there in the database – I can edit it fine, and its summary and featured image pop up fine in the category page.
By which I mean the page 404s whatever the permalink settings are.
OK – I’m investigating pulling out plugins and so on. Will report back.
Deactivate all plugins, revert to Twenty Twelve theme and try again. If the error goes away, activate plugins one by one so that you can know which plugin causes the error. Trying with the default theme will let you know if the problem is theme-specific. You can return to your current settings once the error goes away.
