I have 2 websites with a webmaster working for us on both. I accessed the validation tool on W3C and found that while our home page is ok there are a lot of HTML coding errors on different pages of both our sites (on one particular page, 141 listed by W3C). As a layman, I can't
understand why there should be ANY coding errors, surely that means a mistake that needs to be corrected, like you'd spell check a letter and correct your mistakes. I was given to understand that any HTML coding errors make my site harder to read and therefore less attractive to Googlebot such that this will effect my Page Ranking. I asked him to correct them, his answer as follows:

'they are not coding errors and are created as W3C does not recognise MOD-rewriters, but search engines do and they do not effect SEO or site performance at any level'

I would be grateful for any advice from you guys

It will make absolutely no difference at all to any SEs, and "mod-rewiters" are nothing to do with errors or warnings in HTML code.

The simple answer is ...

Get your webmaster/designer to fix them. If he/she can't


employ someone who can!!

Validation errors numbers are often magnified because one or two errors can sometimes produce a long list of errors and warnings. Quite often you fix those one or two errors and that will correct everything. It could be different but unless we can see the site it's impossible to tell.

Validation errors vary from the html codes used in the page. For example if using image, alt tag is compulsory. So better ask your designer to fix them for you.

alt tag is compulsory

First it's NOT A TAG, it's an ATTRIBUTE!

Secondly, it's only mandatory IF you're using XHTML Strict DOCTYPE