How? IF statement in footer

[smooth-c]

I have a chatbar mod for my board and I want users to be able to disable it if they wish. I have set up a profile field for simply "Yes" or "No" options and i've used this code in my footer template;

<if condition="$bbuserinfo['field17']=='Yes' OR $bbuserinfo['field17']=='No'>
<!-- CometChat Footer Code Start -->
<link type="text/css" rel="stylesheet" media="all" href="/discussion/cometchat/cometchatcss.php" charset="utf-8" />
<script type="text/javascript" src="/discussion/cometchat/cometchatjs.php" charset="utf-8"></script>
<!-- CometChat Footer Code End -->
</if>

I get an error with vb in the admincp saying "Malformed IF statement" - any ideas? Thank you