Hi Janet, thanks for the fast response. As said above this is a fresh install, zero plugins or any content for that matter.
I ran
<?php
phpinfo();
?>
Which neatly reports that I have allocated 128mb to PHP. As for the host, its a VPS so I have full access to the whole machine and any limits.
This is driving me nuts. Thing is that the blogs used to work. Now old and new ones suddenly stopped working.