The HTML5 doctype is not triggering standards mode in IE8

Question

i work for a company where all our sites currently use the XHTML 1.0 transitional doctype (yes i know it is very old school). I want to change them all to use the HTML5 doct

Answer 1

Both the XHTML 1.0 Transitional doctype (when used by the spec, with a URL) and trigger “Standards Mode” in IE. If this does not happen, there is a multitude of reasons that probably have nothing to do with the doctype change (and can only be analyzed if additional information, such as a URL, is available); see IE 8 and IE 9 complications in Activating Browser Modes with Doctype.

Changing to is pointless and a potential problem, unless you not actually changing the markup. In validation, which is the other reason for using doctype, it causes a completely different analysis and quite often error messages about constructs that are valid in XHTML 1.0.