I have a URL which uses this:
However, when I click on it from an email etc it reverts back to http://www.domain.com/page.shtml and drops the ?ref=
Is there a reason why this would happen?
Do you have any rewrite rules defined in an htaccess file? Or any logic in your shtml that may cause it to redirect after the ref is found?
Good thinking! Actually, the rewrite rule would be creating a new (blank?) query string so targeting the offending code should be easy ... if the OP will show his .htaccess file.