It had be a while since I validated my site so I expected to find some problems.
In going to http://validator.w3.org/ I was surprised that the header.php for the default theme did not validate as XHTML Transitional. I knew there was no closing tag for <div> on line 29 but all else should validate AFAIK. There seems to be a particular problem with picking up php as in <? as character data which is nothing I can correct.
Where do I go from here?
I will bump this back to page 1 one time.
I don't know anything about php but I am surprised the header (2.5.1) does not validate. I know 2.3 did. Guess I better check it again . . .
But I would appreciate some insight here.
Raw PHP files don't validate, because they contain PHP code, and PHP code isn't HTML.
Try validating the whole site instead of just the PHP files.
Thank you! I think I used to know that . . . more brain cells seem to be missing.