[Deaths]

Go to ACP-> Styles & Templates -> Edit Templates ->postbit ot postbit_legacy.

Now, find the code for the avatars.
In the postbit template it's this:

PHP Code:

<if condition="$show['avatar']"><td class="alt1"><a href="member.php?$session[sessionurl]u=$post[userid]"><img src="$avatarurl" alt="<phrase 1="$post[username]">$vbphrase[xs_avatar]</phrase>" border="0" /></a></td></if> 


Now, replace that with:

PHP Code:

<if condition="$bbuserinfo[usergroupid]=X">
&nbsp;
<else />
<if condition="$show['avatar']"><td class="alt1"><a href="member.php?$session[sessionurl]u=$post[userid]"><img src="$avatarurl" alt="<phrase 1="$post[username]">$vbphrase[xs_avatar]</phrase>" border="0" /></a></td></if></if> 


Make sure you replace the X with the usergroup you wish to not allow.