So, my first attempt at validating Joomla! involved me pasting in the URI … http://www.stalvies.net/joomla
1 error, but unfortunately … this refers to the whole page!!!
Line 1, Column 0: end of document in prolog.
It doesn’t get any further – it’s giving up on the home page!
Have had similar to this before; normally it’s to do with the DOCTYPE somehow being missed. On this occasion though, I’ve gone so far as to wipe out all characters between the DOCTYPE and <head>, but to no avail!