We've put together a list of the most common errors when validating your sites using http://validator.w3.org/ Markup Vaidation Service. The list will be updated as time permits with other common validation errors and solutions.
w3-Validation tips - specific to Doctype Transitional
Errors (E) and solutions (S) :
E -No DOCTYPE found! S - Add the following Doctype to the top of your pages above the opening <head> tag.
E - No Character Encoding Found! Falling back to UTF-8.
S - After the opening <head> tag check that you have: <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
**Note the above charset maybe different for sites using for foreign characters.
E- end tag for "meta" omitted, but OMITTAG NO was specified
S- meta tag will need to be a self closing tag with / on the end - Example <meta name="keywords" content="keyword, keyword, keyword />
E - There is no attribute "height" or There is no attribute "width" or there is no attribute "bordercolor" .
S - Remove height, width or bordercolor attribute from page, if height or width or border color is needed create a class in the style sheet for page element and assign class to element.
E - There is no attribute "background"
S - Create a class in the style sheet and assign the class to the table/cell.
E - Required attribute "alt" not specified
S - Include alt tags on all images, alt tags can reflect name of product or indicate action required. Alt tags can be empty see examples below. Alt tags are seen by users in some browsers unless left empty. Don't use alt tags as a way to spam search engines as it can cause unexpected negative results.
Version 5.6.0 saw a lot of changes to move the code to XHTML 1.0 Transitional and Section 508 (accessibility) compliance. To take advantage if this new feature you will need to add the following to vsadmin/includes.php or vsadmin/includes.asp