Every time I create a new post from the dashboard, when I tag the post with either an existing tag or a completely new tag, once the new post is saved and I view the page and click on the tag hyperlink, the resulting page is as follows:
The website encountered an error while retrieving http://www.woodleighschool.com/index.php/tag/earth-sciences/. It may be down for maintenance or configured incorrectly.
I believe this is a 500 error.
Tried disabling all plugins with no effect.
Tried resetting the custom permalinks with no effect.
Repaired and optimised the sql database with no effect.
The website was migrated from a wordpress.com site. All the tags from previous posts work, unless a new post add the same tag, in which case it will result in the server error for that tag. Eg tags for "2010" work fine, but if I add "2010" as a tag on a new post, the tag page for "2010" results in a server error.
Once a tag is removed from the new post eg "2010", the tag page works fine and displays all previous posts tagged "2010".
Currently it means that we can't tag any new posts - which is really awkward.