Unable to Validate HTML

errors point to url strings in the pages links

[cfe_admin]

Trying to validate my site, but keep running into a series of errors I don't understand. They all are some variation of this:
--------------------------
Warning Line 124, Column 34: cannot generate system identifier for general entity "id".

<a href="index.php?main_page=page&id=9&chapter=0">
--------------------------

It then underlines the id part right our of the link URL. It's parsing the link strings? How can I avoid/fix this?

Thanks!

[g1smd]

Those need to be coded as &amp; instead of just & each time.

The browser will still get it right when it reads the page.