This evening I’ve been playing with the WP-cache plugin. If you install it and find this error:
Then all you have to do is browse to the wp-cache config file which you should find in the /wp-content/ directory.
Take a copy of the file and open it to edit as follows:
Done. Of course you could try the WP-super-cache plugin, which is an improvement over this one – but brings a new set of potential problems. On first install my entire site started delivering blank HTML. Be careful :-)