Forum Moderators: not2easy
[edited by: SuzyUK at 11:13 pm (utc) on Nov. 20, 2007]
[edit reason] No specifics, thank you [/edit]
Use a valid document type. [webmasterworld.com]
Validate your code. [validator.w3.org]
You have used the attribute named above in your document, but the document type you are using does not support that attribute for this element. This error is often caused by incorrect use of the "Strict" document type with a document that uses frames (e.g. you must use the "Transitional" document type to get the "target" attribute), or by using vendor proprietary extensions such as "marginheight" (this is usually fixed by using CSS to achieve the desired effect instead).
This error may also result if the element itself is not supported in the document type you are using, as an undefined element will have no supported attributes; in this case, see the element-undefined error message for further information.
You have used the attribute named above in your document,
LOL! What's the name of the attribute? :-)
The validator can be tricky, sometimes a single error can "cascade" throughout a document showing a page full of errors when it's just one, or the error may not be the real problem. I'm going to take a wild guess, being it's probably the first one on the list, and this is a good example anyway:
<body marginheight="0" topmargin="0">
This is an old-school way of removing all margins from the top of page content that has long since been replaced by CSS. Neither of the attributes applied to the body tag in this example are supported in all browsers, one is for MS browsers and one is for Mozilla-based browsers. In modern coding, they are both considered invalid and should be replaced by
body { margin:0; padding:0; }
<body>
This makes a good example on two points: with a valid document type, the above will always kick an error in validating - more importantly, in your case, it's one that can be ignored if it's the only error - it will not "break" your layout. Making this assessment is not something a validator will do for you, you will have to understand why you're getting the validation error and decide if it's important to fix or ignore.
Now that you know what attributes are, start with the first error. Make sure you are using a valid method of implementing that attribute, or if the attribute itself is invalid for your selected doctype, find an alternative method of achieving the same effect. A good reference is located at W3C Schools [w3schools.com].
Since you're new here I will suggest that for anyone to help with such problems you can paste the code in a post, but try to eliminate excess information - trim it down to the bare essentials of the problem (and remove all identifying references per the TOS.)
This is also a good way to "debug" cross-browser issues. Strip your page down to it's basic framework. Get that basic framework to validate, then check it in all browsers. Begin slowly re-adding chunks of code, validating, checking browsers, in a trial and error method. When the serious difference crops up, you will know where to look.
