Upgraded from 3.6 to 3.8.8 to get "mark forums read security token was invalid"

[NumNum]

Upgraded from 3.6 to 3.8.8 to pave the way for vb5.1 and get the above error. I hope to resolve this prior to rolling out vb5.1 I have tried the recommended changes listed throughout this forum to no avail. Below is a shot of my edited template. I am obviously missing something. I know this is old school, but I hope someone can help.

PHP Code:

        <td class="vbmenu_control"><a href="forumdisplay.php?$session[sessionurl]do=markread&amp;markreadhash=$bbuserinfo[securitytoken]" rel="nofollow">$vbphrase[mark_forums_read]</a></td>
            <if condition="$show['member']">            
            <td class="vbmenu_control"><a href="#" onclick="window.open('misc.php?$session[sessionurl]do=buddylist&amp;focus=1','buddylist','statusbar=no,menubar=no,toolbar=no,scrollbars=yes,resizable=yes,width=250,height=300'); return false;">$vbphrase[open_buddy_list]</a></td>            
        </if>            
    </if>
    $template_hook[navbar_buttons_right]
    <if condition="$show['member']">
        <td class="vbmenu_control"><a href="login.php?$session[sessionurl]do=logout&amp;logouthash=$bbuserinfo[logouthash]" onclick="return log_out('$vbphrase[sure_you_want_to_log_out]')">$vbphrase[log_out]</a></td>
    </if>
</tr>
</table>
<!-- / nav buttons bar -->

<br />
<if condition="$show['forumdesc']">
    <table class="tborder" cellpadding="$stylevar[cellpadding]" cellspacing="$stylevar[cellspacing]" border="0" width="100%" align="center">
    <tr>
        <td class="alt1" width="100%"><strong>$foruminfo[title]</strong> <span class="smallfont">$foruminfo[description]</span></td>
    </tr>
    </table>
    <br />
</if>

<if condition="$show['popups']">
<!-- NAVBAR POPUP MENUS -->
    
    <if condition="$show['searchbuttons']">
    <!-- header quick search form -->
    <div class="vbmenu_popup" id="navbar_search_menu" style="display:none">
        <table cellpadding="4" cellspacing="1" border="0">
        <tr>
            <td class="thead">$vbphrase[search_forums]</td>
        </tr>
        <tr>
            <td class="vbmenu_option" title="nohilite">
                <form action="search.php?do=process" method="post">
                    <input type="hidden" name="do" value="process" />
                    <input type="hidden" name="quicksearch" value="1" />
                    <input type="hidden" name="childforums" value="1" />
                    <input type="hidden" name="exactname" value="1" />
                    <input type="hidden" name="s" value="$session[sessionhash]" />
    <input type="hidden" name="securitytoken" value="$bbuserinfo[securitytoken]" />
                    <div><input type="text" class="bginput" name="query" size="25" tabindex="1001" /><input type="submit" class="button" value="$vbphrase[go]" tabindex="1004" /></div>
                    <div style="margin-top:$stylevar[cellpadding]px">
                        <label for="rb_nb_sp0"><input type="radio" name="showposts" value="0" id="rb_nb_sp0" tabindex="1002" checked="checked" />$vbphrase[show_threads]</label>
                        &nbsp;
                        <label for="rb_nb_sp1"><input type="radio" name="showposts" value="1" id="rb_nb_sp1" tabindex="1003" />$vbphrase[show_posts]</label>
                    </div>                    
                </form>
            </td>
        </tr>
        <tr>
            <td class="vbmenu_option"><a href="search.php$session[sessionurl_q]" accesskey="4" rel="nofollow">$vbphrase[advanced_search]</a></td>
        </tr>
        $template_hook[navbar_search_menu]
        </table>
    </div>
    <!-- / header quick search form -->
    </if>

    <if condition="$show['member']">
    <!-- user cp tools menu -->
    <div class="vbmenu_popup" id="usercptools_menu" style="display:none">
        <table cellpadding="4" cellspacing="1" border="0">
        
        <tr><td class="thead">$vbphrase[quick_links]</td></tr>        
        <if condition="$vboptions['enablesearches']"><tr><td class="vbmenu_option"><a href="search.php?$session[sessionurl]do=getdaily">$vbphrase[todays_posts]</a></td></tr></if>
        <tr><td class="vbmenu_option"><a href="forumdisplay.php?$session[sessionurl]do=markread">$vbphrase[mark_forums_read]</a></td></tr>